字节跳动一面面经
字节跳动(字节跳动果然很注重算法和编程)
1.写出运行结果
var result = []; var a = 3; var total = 0; function foo(a) { var i = 0; for (; i < 3; i++) { result[i] = function() { total += i * a; console.log(total); } } } foo(1); result[0](); result[1](); result[2]();
2.实现一个二进制加法,输入输出均为二进制字符串
function binaryAdd(num1, num2) {
// TODO
}
//Example
binaryAdd('1010', '111') // '10001'
function binaryAdd(num1, num2) { let len1 = num1.length - 1; let len2 = num2.length - 1; let flag = 0; let result = ''; while (len1 >= 0 || len2 >= 0) { let n1 = len1 < 0 ? 0 : Number(num1[len1]); let n2 = len2 < 0 ? 0 : Number(num2[len2]); if (n1 == 1 && n2 == 1) flag = 1; let sum = n1 + n2 + flag; if (sum > 1) result += 0; else result += 1; len1--;len2--; } if (flag == 1) result += 1; } //Example binaryAdd('10101', '1111') // '10001'
3.实现一个函数a,使其奇数次调用时返回1,偶数次调用时返回2(不能使用全局变量)
var a = (function () { var index = 1; function b() { if (index % 2 == 1) { console.log(1); } else { console.log(2); } index++; } return b })() a();//1 a();//2 a();//1
4.crsf原理
5.事件委托机制
#字节跳动##前端工程师#