模拟
class Solution { public: string solve(string s, string t) { int len1 = s.size(); int len2 = t.size(); reverse(s.begin(), s.end()); reverse(t.begin(), t.end()); vector<int> v(max(len1, len2)+10, 0); for (int i = 0; i < max(len1, len2); i++) { if (i < len1) { v[i] += s[i]-'0'; } if (i < len2) { v[i] += t[i]-'0'; } } int temp = 0; for (int i = 0; i < v.size(); i++) { v[i] += temp; temp = v[i] / 10; v[i] %= 10; } int f = 0; string ans; for (int i = v.size() - 1; i >= 0; i--) { if (f == 0 && v[i] == 0) continue; f = 1; ans.push_back(v[i] + '0'); } if (!ans.size()) return "0"; return ans; } };