正则表达式 count() , toString() 转进制
求int型正整数在内存中存储时1的个数
https://www.nowcoder.com/practice/440f16e490a0404786865e99c6ad91c9
const readline = require("readline");
const rl = readline.createInterface({
input: process.stdin,
output: process.stdout,
});
rl.on("line", function (line) {
const tokens = line.split(" ");
// TODO: code start
console.log((parseInt(tokens[0]).toString(2).match(/1/g) || []).length);
});