大数除法

#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;

vector<int> div (vector<int> &A, int &b, int &r)
{
    vector<int> C;
    r=0;
    for(int i = A.size()- 1 ;i >= 0 ;i --  ) {
        r = r * 10 + A[i];
        C.push_back(r / b);
        r %= b;
    }
    reverse(C.begin(), C.end());
    while(C.size() > 1 && C.back() == 0 ) C.pop_back();
    return C;
}


int main()
{
    string a;
    int b;
    cin>>a>>b;
    vector<int> A;
    for(int i = a.size()- 1 ;i >= 0; i --) A.push_back(a[i]-‘0‘);
    
    int r=0;
    auto C = div(A , b , r);
    for(int i = C.size()- 1 ;i >= 0; i -- ) cout<<C[i];
    cout<<endl<<r<<endl;
    return 0;
}