题解 | #高精度整数加法#

#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

int main() {
    string a, b;
    cin >> a >> b;

    string result;

    if (a.size() > b.size()) swap(a, b);
    int len = b.size();
    string pad(len - a.size(), '0');
    a = pad + a;

    int asd = 0;
    for (int i = 1; i <= len; ++i) {
        int num = a[len - i] - '0' + b[len - i] - '0';
        num += asd;
        asd = num > 9 ? 1 : 0;
        num %= 10;
        result += to_string(num);
    }
    if (asd == 1) result += '1';

    reverse(result.begin(), result.end());

    cout << result << endl;
}
// 64 位输出请用 printf("%lld")