js基础

三种基础循环打印99乘法表

1. for

for (let i = 1; i < 10; i++) {
    for (let j = 1; j <= i; j++) {
        console.log(i, j);
    }
}

2. while

let i = 1
while (i < 10) {
    let j = 1
    while (j <= i) {
        console.log(i, j);
        j++
    }
    i++
}

3. do{}while

let i = 1;
do {
    let j = 1
    do {
        console.log(i, j);
        j++
    } while (j <= i)
    i++
} while (i < 10);