多重循环和程序调试

一，多重循环

 

 

例如：
//乘法表
for (int i =1;i <= 9; i++){
    for (int j=1;j <= i; j++){
        int num = i * j;
        if (num > 9) {
            System.out.print(i + "*" + j + "=" + num + "  ");
        }else{
            System.out.print(i + "*" + j + "=" + num + "   ");
        }
    }
    for (int j=9;j >= 1; j--){
        System.out.print("      ");
    }
    System.out.println();
}

 

 

 

//输出等腰三角形

for (int i= 1; i <= 5; i++){
    for (int j = 1; j <= 5-i; j++){
        System.out.print(" ");
    }
    for (int j = 1;j <= 2*i-1; j++){
        System.out.print("*");
    }
    System.out.println();
}