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Fix whitespace
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Adam
parent
776fe991c6
commit
ba55f6fcaa
@ -15,173 +15,173 @@ Read more here: https://en.wikipedia.org/wiki/Java_(programming_language)
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///////////////////////////////////////
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// General
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///////////////////////////////////////
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// Single-line comments start with //
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/*
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Multi-line comments look like this.
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*/
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// Single-line comments start with //
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/*
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Multi-line comments look like this.
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*/
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// Import Packages
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import java.util.ArrayList;
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import package.path.here;
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// Import all "sub-packages"
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import java.lang.Math.*;
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// Import Packages
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import java.util.ArrayList;
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import package.path.here;
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// Import all "sub-packages"
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import java.lang.Math.*;
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// Your program's entry point is a function called main
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public class Main
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{
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// Your program's entry point is a function called main
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public class Main
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{
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public static void main (String[] args) throws java.lang.Exception
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{
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//stuff here
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}
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}
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}
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// Printing, and forcing a new line on next print = println()
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System.out.println("Hello World");
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System.out.println("Integer: "+10+"Double: "+3.14+ "Boolean: "+true);
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// Printing, without forcing a new line on next print = print()
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System.out.print("Hello World");
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System.out.print("Integer: "+10+"Double: "+3.14+ "Boolean: "+true);
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// Printing, and forcing a new line on next print = println()
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System.out.println("Hello World");
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System.out.println("Integer: "+10+"Double: "+3.14+ "Boolean: "+true);
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// Printing, without forcing a new line on next print = print()
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System.out.print("Hello World");
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System.out.print("Integer: "+10+"Double: "+3.14+ "Boolean: "+true);
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///////////////////////////////////////
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// Types
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///////////////////////////////////////
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// Byte - 8-bit signed two's complement integer (-128 <= byte <= 127)
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byte foo = 100;
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// Byte - 8-bit signed two's complement integer (-128 <= byte <= 127)
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byte foo = 100;
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// Short - 16-bit signed two's complement integer (-32,768 <= short <= 32,767)
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short bar = 10000;
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// Short - 16-bit signed two's complement integer (-32,768 <= short <= 32,767)
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short bar = 10000;
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//Integer - 32-bit signed two's complement integer (-2,147,483,648 <= int <= 2,147,483,647)
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int foo = 1;
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//Integer - 32-bit signed two's complement integer (-2,147,483,648 <= int <= 2,147,483,647)
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int foo = 1;
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//Long - 64-bit signed two's complement integer (-9,223,372,036,854,775,808 <= long <= 9,223,372,036,854,775,807)
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long bar = 100000L;
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//Long - 64-bit signed two's complement integer (-9,223,372,036,854,775,808 <= long <= 9,223,372,036,854,775,807)
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long bar = 100000L;
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//Float - Single-precision 32-bit IEEE 754 Floating Point
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float foo = 234.5f;
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//Float - Single-precision 32-bit IEEE 754 Floating Point
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float foo = 234.5f;
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//Double - Double-precision 64-bit IEEE 754 Floating Point
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double bar = 123.4;
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//Double - Double-precision 64-bit IEEE 754 Floating Point
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double bar = 123.4;
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//Boolean - True & False
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boolean foo = true;
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boolean bar = false;
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//Boolean - True & False
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boolean foo = true;
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boolean bar = false;
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//Char - A single 16-bit Unicode character
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char foo = 'A';
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//Char - A single 16-bit Unicode character
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char foo = 'A';
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//Make a variable a constant
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final int HOURS_I_WORK_PER_WEEK = 9001;
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//Make a variable a constant
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final int HOURS_I_WORK_PER_WEEK = 9001;
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//Strings
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String foo = "Hello World!";
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// \n is an escaped character that starts a new line
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String foo = "Hello World!\nLine2!";
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System.out.println(foo);
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//Hello World!
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//Line2!
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//Strings
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String foo = "Hello World!";
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// \n is an escaped character that starts a new line
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String foo = "Hello World!\nLine2!";
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System.out.println(foo);
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//Hello World!
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//Line2!
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//Arrays
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//The array size must be decided upon declaration
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//The format for declaring an array is follows:
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//<datatype> [] <var name> = new <datatype>[<array size>];
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int [] array = new int[10];
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String [] array = new String[1];
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boolean [] array = new boolean[100];
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//Arrays
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//The array size must be decided upon declaration
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//The format for declaring an array is follows:
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//<datatype> [] <var name> = new <datatype>[<array size>];
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int [] array = new int[10];
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String [] array = new String[1];
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boolean [] array = new boolean[100];
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// Indexing an array - Accessing an element
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array[0];
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// Indexing an array - Accessing an element
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array[0];
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// Arrays are mutable; it's just memory!
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array[1] = 1;
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System.out.println(array[1]); // => 1
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array[1] = 2;
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System.out.println(array[1]); // => 2
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// Arrays are mutable; it's just memory!
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array[1] = 1;
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System.out.println(array[1]); // => 1
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array[1] = 2;
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System.out.println(array[1]); // => 2
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//Others to check out
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//ArrayLists - Like arrays except more functionality is offered, and the size is mutable
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//LinkedLists
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//Maps
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//HashMaps
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//Others to check out
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//ArrayLists - Like arrays except more functionality is offered, and the size is mutable
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//LinkedLists
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//Maps
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//HashMaps
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///////////////////////////////////////
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// Operators
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///////////////////////////////////////
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int i1 = 1, i2 = 2; // Shorthand for multiple declarations
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int i1 = 1, i2 = 2; // Shorthand for multiple declarations
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// Arithmetic is straightforward
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i1 + i2; // => 3
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i2 - i1; // => 1
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i2 * i1; // => 2
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i1 / i2; // => 0 (0.5, but truncated towards 0)
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// Arithmetic is straightforward
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i1 + i2; // => 3
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i2 - i1; // => 1
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i2 * i1; // => 2
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i1 / i2; // => 0 (0.5, but truncated towards 0)
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// Modulo
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11 % 3; // => 2
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// Modulo
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11 % 3; // => 2
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// Comparison operators
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3 == 2; // => 0 (false)
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3 != 2; // => 1 (true)
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3 > 2; // => 1
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3 < 2; // => 0
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2 <= 2; // => 1
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2 >= 2; // => 1
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// Comparison operators
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3 == 2; // => 0 (false)
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3 != 2; // => 1 (true)
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3 > 2; // => 1
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3 < 2; // => 0
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2 <= 2; // => 1
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2 >= 2; // => 1
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// Bitwise operators!
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~ Unary bitwise complement
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<< Signed left shift
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>> Signed right shift
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>>> Unsigned right shift
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& Bitwise AND
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^ Bitwise exclusive OR
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| Bitwise inclusive OR
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// Bitwise operators!
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~ Unary bitwise complement
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<< Signed left shift
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>> Signed right shift
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>>> Unsigned right shift
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& Bitwise AND
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^ Bitwise exclusive OR
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| Bitwise inclusive OR
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// Incrementations
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int i=0;
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i++; //i = 1. Post-Incrementation
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++i; //i = 2. Pre-Incrementation
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i--; //i = 1. Post-Decrementation
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--i; //i = 0. Pre-Decrementation
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// Incrementations
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int i=0;
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i++; //i = 1. Post-Incrementation
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++i; //i = 2. Pre-Incrementation
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i--; //i = 1. Post-Decrementation
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--i; //i = 0. Pre-Decrementation
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///////////////////////////////////////
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// Control Structures
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///////////////////////////////////////
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if (false) {
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if (false) {
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System.out.println("I never run");
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} else if (false) {
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System.out.println("I am also never run");
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} else {
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System.out.println("I print");
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}
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}
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}
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// While loop
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int i = 0;
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while(i < 100){
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// While loop
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int i = 0;
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while(i < 100){
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System.out.println(i);
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//Increment the counter
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i++;
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}
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}
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// Do While Loop
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int i = 0;
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do{
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// Do While Loop
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int i = 0;
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do{
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System.out.println(i);
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//Increment the counter
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i++;
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}while(i < 100);
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}while(i < 100);
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// For Loop
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int i;
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//for loop structure => for(<start_statement>;<conditional>;<step>)
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for(i=0;i<100;i++){
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// For Loop
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int i;
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//for loop structure => for(<start_statement>;<conditional>;<step>)
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for(i=0;i<100;i++){
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System.out.println(i);
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}
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}
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// Switch Case
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int month = 8;
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// Switch Case
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int month = 8;
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String monthString;
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switch (month) {
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case 1: monthString = "January";
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@ -217,35 +217,35 @@ Read more here: https://en.wikipedia.org/wiki/Java_(programming_language)
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// Typecasting
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///////////////////////////////////////
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// Converting data
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// Converting data
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//Convert String To Integer
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Integer.parseInt("123");//returns an integer version of "123"
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//Convert String To Integer
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Integer.parseInt("123");//returns an integer version of "123"
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//Convert Integer To String
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Integer.toString(123);//returns a string version of 123
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//Convert Integer To String
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Integer.toString(123);//returns a string version of 123
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//For other conversions check out the following classes:
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//Double
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//Long
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//String
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//For other conversions check out the following classes:
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//Double
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//Long
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//String
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// You can also cast java objects, there's a lot of details and
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// deals with some more intermediate concepts.
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// Feel free to check it out here: http://docs.oracle.com/javase/tutorial/java/IandI/subclasses.html
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// You can also cast java objects, there's a lot of details and
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// deals with some more intermediate concepts.
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// Feel free to check it out here: http://docs.oracle.com/javase/tutorial/java/IandI/subclasses.html
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///////////////////////////////////////
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// Classes And Functions
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///////////////////////////////////////
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// Classes Syntax shown below.
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// Function declaration syntax:
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// <public/private/protected> <return type> <function name>(<args>)
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// Here is a quick rundown on access level modifiers (public, private, etcetc) http://docs.oracle.com/javase/tutorial/java/javaOO/accesscontrol.html
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// Classes Syntax shown below.
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// Function declaration syntax:
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// <public/private/protected> <return type> <function name>(<args>)
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// Here is a quick rundown on access level modifiers (public, private, etcetc) http://docs.oracle.com/javase/tutorial/java/javaOO/accesscontrol.html
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public class Bicycle {
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public class Bicycle {
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// Bicycle's Fields/Variables
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public int cadence;
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@ -285,11 +285,11 @@ Read more here: https://en.wikipedia.org/wiki/Java_(programming_language)
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speed += increment;
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}
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}
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}
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//Now..Later in the main / driver of your java program
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public class Main
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{
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//Now..Later in the main / driver of your java program
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public class Main
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{
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public static void main (String[] args) throws java.lang.Exception
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{
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//Call bicycle's constructor
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@ -298,7 +298,7 @@ Read more here: https://en.wikipedia.org/wiki/Java_(programming_language)
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trek.speedUp(3);
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trek.setCadence(100);
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}
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}
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}
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```
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@ -306,14 +306,14 @@ Read more here: https://en.wikipedia.org/wiki/Java_(programming_language)
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Other Topics To Research:
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* Inheritance (http://en.wikipedia.org/wiki/Inheritance_(object-oriented_programming))
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* Inheritance (http://en.wikipedia.org/wiki/Inheritance_(object-oriented_programming))
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* Abstraction (http://en.wikipedia.org/wiki/Abstraction_(computer_science))
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* Abstraction (http://en.wikipedia.org/wiki/Abstraction_(computer_science))
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* Exceptions (http://en.wikipedia.org/wiki/Exception_handling)
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* Exceptions (http://en.wikipedia.org/wiki/Exception_handling)
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* Interfaces (http://en.wikipedia.org/wiki/Interfaces_(computer_science))
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* Interfaces (http://en.wikipedia.org/wiki/Interfaces_(computer_science))
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* Generics (http://en.wikipedia.org/wiki/Generics_in_Java)
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* Generics (http://en.wikipedia.org/wiki/Generics_in_Java)
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* The links provided are just to get an understanding of the topic, feel free to google and find specific examples
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* The links provided are just to get an understanding of the topic, feel free to google and find specific examples
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@ -111,7 +111,7 @@ except NameError:
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print "Raises a name error"
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# if can be used as an expression
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some_var = a if a > b else b
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some_var = 1 if 1 > 2 else 2 # => 2
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# If a is greater than b, then a is assigned to some_var.
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# Otherwise b is assigned to some_var.
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@ -207,8 +207,11 @@ filled_dict.values() #=> [3, 2, 1]
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"one" in filled_dict #=> True
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1 in filled_dict #=> False
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# Trying to look up a non-existing key will raise a KeyError
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filled_dict["four"] #=> KeyError
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try:
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# Trying to look up a non-existing key will raise a KeyError
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filled_dict["four"] #=> KeyError
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except KeyError:
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pass
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# Use get method to avoid the KeyError
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filled_dict.get("one") #=> 1
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@ -235,7 +238,7 @@ filled_set = {1, 2, 2, 3, 4} # => {1 2 3 4}
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filled_set.add(5) # filled_set is now {1, 2, 3, 4, 5}
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# Do set intersection with &
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other_set = set{3, 4, 5, 6}
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other_set = {3, 4, 5, 6}
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filled_set & other_set #=> {3, 4, 5}
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# Do set union with |
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@ -337,7 +340,7 @@ def keyword_args(**kwargs):
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keyword_args(big="foot", loch="ness") #=> {"big": "foot", "loch": "ness"}
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# You can do both at once, if you like
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def all_the_args(*args, **kwargs):
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def foo(*args, **kwargs):
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print args
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print kwargs
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"""
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