高精度加法

#include<bits/stdc++.h>
using namespace std;
vector<int> add_num(vector<int>&a, vector<int>&b){
    if(a.size() < b.size())return add_num(b, a);
    vector<int>c;
    int k = 0;
    for(int i = 0; i < a.size(); i++){
        k += a[i];
        if(i < b.size()){
            k += b[i];
        }
        c.push_back(k % 10);
        k /= 10;
    }
    if(k)c.push_back(k);
    return c;
}
int main(){
    string a, b;
    vector<int>u, v, c;
    cin >> a >> b;
    for(int i = a.size() - 1; i >= 0; i--)u.push_back(a[i] - '0');
    for(int i = b.size() - 1; i >= 0; i--)v.push_back(b[i] - '0');
    c = add_num(u, v);
    for(int i = c.size() - 1; i >= 0; i--)cout << c[i];
    return 0;
}