#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
string add(string s, string s2) {
string maxstr, minstr;
if(s.length() > s2.length()) {
maxstr = s;
minstr = s2;
} else {
maxstr = s2;
minstr = s;
}
int l = maxstr.length();
int l2 = minstr.length();
for(int i = l - 1, j = l2 - 1; j >= 0; i--, j--) {
maxstr[i] += minstr[j] - '0';
}
for(int i = l - 1; i >= 1; i--) {
if(maxstr[i] > '9') {
maxstr[i] -= 10;
maxstr[i - 1]++;
}
}
if(maxstr[0] > '9') {
maxstr[0] -= 10;
maxstr = '1' + maxstr;
}
int i = 0;
for(; i < maxstr.size(); i++) {
if(maxstr[i] != '0') {
break;
}
}
if(i == maxstr.size()) {
return "0";
} else {
return maxstr.erase(0, i);
}
}
int main() {
return 0;
}