如标题

#include <bits/stdc++.h>
using namespace std;

const int N=509;
int lena, a[N];
int lenb, b[N];
int lend, d[N];
int pon;

int main(){
    for (char c=getchar(); c!='\n'; c=getchar()){
        lena++;
        a[lena]=c-'0';
    }

    for (char c=getchar(); c!='\n'; c=getchar()){
        lenb++;
        b[lenb]=c-'0';
    }

    for (int p1=1, p2=lena; p1<p2; ++p1, --p2){
        int c=a[p1];
        a[p1]=a[p2];
        a[p2]=c;
    }

    for (int p1=1, p2=lenb; p1<p2; ++p1, --p2){
        int c=b[p1];
        b[p1]=b[p2];
        b[p2]=c;
    }

    if(lena>lenb)
        lend=lena;
    else
        lend=lenb;

    for(int i=1;i<=lend;i++){
        d[i]=a[i] + b[i] + pon;
        pon=0;
        if(d[i]>=10){
            d[i]-=10;
            d[i+1]++;
            pon=1;
        }
    }
    if(d[lend+1]==1){
        lend++;
    }
    for (int i=lend; i>=1; --i) cout << d[i];
    cout <<endl;
!
    return 0;
}