$$\color{red}{算法}\color{blue}{基础课}\color{purple}{笔记and题解}\color{green}{汇总}$$
笔记：
高精除以低精。
依次把每一位加进余数，除以$b$，最后再取模。

代码：

#include <bits/stdc++.h>
using namespace std;
string a;
vector<int> A;
int B, c;
vector<int> div(vector<int> &A, int b, int &r) {
    vector<int> C;
    c = 0;
    for (int i = A.size() - 1; i >= 0; i--) {
        c = c * 10 + A[i];
        C.push_back(r / b);
        c %= b;
    }
    reverse(C.begin(), C.end());
    while (C.size() > 1 && C.back() == 0) C.pop_back();
    return C;
}
int main() {
    cin >> a >> B;
    for (int i = a.size() - 1; i >= 0; i--) A.push_back(a[i] - '0');
    auto C = div(A, B, c);
    for (int i = C.size() - 1; i >= 0; i--) cout << C[i];
    printf("\n%d\n", c);
    return 0;
}