高精度+高精度（信息学奥赛1168）

#include <iostream>
#include <cmath>
#include <vector>
using namespace std;
int main(){
    string a,b;
    cin>>a>>b;
    bool a1 = true,b1 = true;
    for(int i = 0;i<max(a.size(),b.size());i++){
        if(i<a.size() && a[i]!='0'){
            if(a1){
                a = a.substr(i);
                a1 = false;
            }
        }
        if(i<b.size() && b[i]!='0'){
            if(b1){
                b = b.substr(i);
                b1 = false;
            }
        }
    }
    vector<int> x,y,sum;
    for(int i = a.size()-1;i>=0;i--){
        x.push_back(a[i]-'0');
    }
    for(int i = b.size()-1;i>=0;i--){
        y.push_back(b[i]-'0');
    }
    int j = 0;
    for(int i = 0;i<max(x.size(),y.size()) || j;i++){
        if(i<x.size()){
            j += x[i];
        }
        if(i<y.size()){
            j += y[i];
        }
        sum.push_back(j%10);
        j /= 10;
    }
    for(int i = sum.size()-1;i>=0;i--){
        cout<<sum[i];
    }
    return 0;
}