js寻找质数

js寻找小于指定数字的质数：

let x = prompt('请输入要找的素数', 10)
let need =[]
iprime:
for (n = 2; n < x; n++) {
    for (m = 2; m < n; m++) {
        if (n%m==0){
            continue iprime;
        }
    }
    alert(n)
}