大整数加法
2019-12-26 本文已影响0人
sullay
/**
* 腾讯笔试: 大整数加法
*
* 实现大整数相加算法，两个数用字符串模拟函数原型：
* function add(a, b) {}
* @param {string} a
* @param {string} b
* @return {string} - a b 之和
*
* 测试用例如下：
* 用例1: console.log(add('999', '1') === '1000');
* 用例2: console.log(add('1', '999') === '1000');
* 用例3: console.log(add('123', '123') === '246');
* 用例4: console.log(add('999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999', '1')==='1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000')
*/
function add(a, b) {
let res = ""
let c = 0
a = a.split('')
b = b.split('')
while (a.length > 0 || b.length > 0 || c > 0) {
c = ~~a.pop() + ~~b.pop() + c
res = c % 10 + res
c >= 10 ? c = 1 : c = 0
}
return res.replace(/^0+/, '')
}
console.log(add('00999', '1') === '1000');
console.log(add('1', '999') === '1000');
console.log(add('123', '123') === '246');
console.log(add('999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999', '1') === '1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000')
