javascript循环语句,javascript语句

计算一个数的绝对值

function abs(x) { if (x >= 0) { return x; } else { return -x; }}console.log(abs(10) === abs(-10)); //=>true

计算数组元素之和

let arr = [1, 3, 5];function sum(array) { let sum = 0; for (let x of array) {//循环数组把每个元素赋给x sum += x; } return sum;}console.log(sum(arr));

计算阶乘（1）

function factorial(n) { let product = 1;//乘积初始化为1 while (n > 1) { product *= n; n--; } return product;}console.log(factorial(4));//=> 24:1*4*3*2

计算阶乘（2）

function factorial2(n) { let product = 1; for (i = 2; i <= n; i++) { product *= i; } return product;}console.log(factorial2(4));//=>24:1*2*3*4