66. Plus One（js）

66. Plus One

Given a non-empty array of digits representing a non-negative integer, plus one to the integer.

The digits are stored such that the most significant digit is at the head of the list, and each element in the array contain a single digit.

You may assume the integer does not contain any leading zero, except the number 0 itself.

Example 1:

Input: [1,2,3]
Output: [1,2,4]
Explanation: The array represents the integer 123.

Example 2:

Input: [4,3,2,1]
Output: [4,3,2,2]
Explanation: The array represents the integer 4321.
题意：给定一个数组，数组项从前往后分别是一个从高位到低位组成的数字，在这个数字上加1，然后再变成数组返回
代码如下：

/**
 * @param {number[]} digits
 * @return {number[]}
 */
var plusOne = function(digits) {
   let len=digits.length;
    for(let i=len-1;i>=0;i--){
        if(digits[i]<9){
            ++digits[i];
            return digits;
        }
        digits[i]=0;
    }
    let res=[];
    res[0]=1;
    for(let i=0;i<len;i++){
        res.push(0);
    }
    return res;

};