答案

#include<bits/stdc++.h>
using namespace std;
int a[105],b[105],c[105];
int main(){
string s1,s2; cin >> s1 >> s2;
int l1 = s1.size(),l2 = s2.size();
for(int i = 0;i < l1;i++) a[l1 - i - 1] = s1[i] - '0';
for(int i = 0;i < l2;i++) b[l2 - i - 1] = s2[i] - '0';
int l = max(l1,l2);
for(int i = 0;i < l;i++){
c[i] += a[i] + b[i];
if(c[i] >= 10){
c[i] -= 10;
c[i + 1]++;
}
}
while(c[l] == 0) l--;
for(int i = l;i >= 0;i--) cout << c[i];
return 0;
}