Java Cheat Sheet by yuyu

package com.company;

import java.lang.System;

public class Main {

    public static void swap(int[] list, int e1, int e2)
    {
        int temp;
        temp = list[e1];
        list[e1] = list[e2];
        list[e2] = temp;

        System.out.print("\nafter swap: ");
        for (int i = 0; i < 5; i++)
        {
            System.out.print(list[i] + " ");
        }

    }

    public static void main(String[] args)
    {
        int [] mylist = new int [] {1, 2, 3, 4, 5};

        System.out.print("before swap: ");
        for (int i = 0; i < 5; i++)
        {
            System.out.print(mylist[i] + " ");
        }

        swap(mylist, 1, 2);
        swap(mylist, 0, 4);
        swap(mylist, 1, 3);
    }
}

- List use when shopping
- can make 2 ways:

int[] ex1 = new int [3];
ex1[0]= 1;
ex2[1]= 2;
ex3[2]= 3;

While loops

        int count = 0;
        while (count < mylist.lenght) {
            System.out.print( mylist[count] + "");
            
            count ++;

- It make the code run and check the condition.
(if the condition correct or not and have 1 letter)

int count=0;
do{
         System.out.print(count + " ");
         count ++ ;
}while (count < 10);

Ans 0 1 2 3 4 5 6 7 8 9

 For loops (do everything in () )
            Characters
            String name = "yuyu";
               for (char y : name.toCharArray()){
                   System.out.print(y + " ");
               }
            Ans y u y u 
                    
                int [] mylist = {2,4,6};
                for (int i = 0; i < mylist.length; i++)
                {
                    System.out.print( mylist [i] + " ");
                }
            Ans 2 4 6