Java流程控制语句有哪些举例详解

//正确的顺序
int i = 10;
System.out.println(i);
//错误的顺序
System.out.println(i);
int i = 20;

int i = 10;
if(i == 10){
System.out.println("i等于10");}//输出i等于10

int i = 20;
if(i == 10){
System.out.println("i等于10");}else{
System.out.println("i不等于10");
}//输出i等于10

int i = 50;
if(i == 10){
System.out.println("i等于10");}else if(i == 20){
System.out.println("i等于20");}else{
System.out.println("i不等于10也不等于20");`}//输出i不等于10也不等于20

int i = 50;
if(i > 10){
    if(i > 20){
      
    }else{ }
}else{
  
}else{ }

int i = 10;
switch(i){
case 10:
System.out.println("i等于10");
break;
case 20:
System.out.println("i等于20");}

for(int i = 1;i <= 10;i++){
System.out.println("i等于" + i);
}

int i = 1;
while(i <= 10){
System.out.println("i等于" + i);
i++;//记得迭代，否则会死循环
}

int i = 1;  
do{
System.out.println("i等于" + i);
i++;}//记得更新值，否则会死循环
while(i <= 10);

for(int i = 1;i <= 9;i++){
for(int j = 1;j <= i;j++){
System.out.print(j + "*" + i + "=" + (j * i) + "\t");
}
System.out.println();
}

for(int i = 2;i <= 100;i++){
boolean isPrime = true;
for(int j = 2;j < i;j++){
if(i % j == 0){
isPrime = false;
break;}
}
if(isPrime){
System.out.println(i);
}

for(int i = 100;i <= 999;i++){
int ge = i % 10;
int shi = i / 10 % 10;
int bai = i / 100;
if(i == ge * ge * ge + shi * shi * shi + bai * bai * bai){
System.out.println(i);}
}

        for (int i = 1; i <= 5; i++) {
            //上半部分
            for (int j = 1; j <= 10 - 2 * i; j++) {
                System.out.print(" ");
            }
            for (int k = 1; k <= 2 * i - 1; k++) {
                System.out.print("* ");
            }
            System.out.println();
        }
        for(int i=1;i<=4;i++){
            //下半部分
            for(int j=1;j<=2*i;j++){
                System.out.print(" ");
            }
            for(int k=1;k<=10-2*i-1;k++){
                System.out.print("* ");
            }
            System.out.println();
        }

import java.util.Scanner;
public class ScannerDemo {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入一个整数：");
        int num = sc.nextInt();
        System.out.println("您输入的整数是：" + num);
        sc.close();
    }
}