C++ 代码

#include<iostream>
#include<cstring>
using namespace std;
const int N = 100010;
int a[N],b[N],c[N];

int main(){
    int lena,lenb,lenc;
    string s1,s2;
    cin>>s1>>s2;
    lena=s1.length();
    lenb=s2.length();
    //倒序存储
    for(int i=0;i<lena;i++)
        a[i] = s1[lena-i-1] - '0';

    for(int i=0;i<lenb;i++)
        b[i] = s2[lenb-i-1] - '0';
    //从低位向高位累加
    lenc = max(lena,lenb);
    for(int i=0;i<lenc;i++){
        c[i] = a[i]+b[i]+c[i];
        c[i+1] = c[i] / 10;
        c[i] %= 10;
    }
    if(c[lenc]) lenc++;//处理最高进位

    for(int i=lenc-1;i>=0;i--)
        cout<<c[i];

    return 0;
}