leetcode-华为专题-989. 数组形式的整数加法

 

 

class Solution {
public:
    vector<int> addToArrayForm(vector<int>& num, int k) {
        vector<int> vec;
        string str_k = to_string(k);
        // cout<<"num: "<<num.size()<<" "<<str_k.length()<<endl;

        vector<int> res;
        int i = str_k.size()-1;
        int j = num.size()-1;
        int sum = 0;
        int cur = 0;
        int high = 0;
        int temp = 0;
        while((j>=0||i>=0)){
            if(i>=0&&j>=0){  // 两个一样长
                temp = num[j]+(str_k[i]-'0');
            }else if(j>=0&&i<0){ // 一长一短
                temp = num[j];
            }else if(i>=0&&j<0){
                temp = str_k[i]-'0';
            }
            cur = (temp+high)%10;  // 当前为等于（两数当前位之和+上次的进位）%10
            high = (temp+high)/10;  // 进位等于（两数当前位之和+上次的进位）/10
            // sum = sum * 10 + cur;
            res.push_back(cur);
            j--;
            i--;
        }
        if(high>0) // 如果最高位存在进位，加上
            res.push_back(high);
        
        for(int i = 0; i < res.size(); i++){
            cout<<i<<" : "<<res[i]<<endl;
        }
        reverse(res.begin(), res.end()); // 反转
        return res;
    }
};