题解 | 递推数列

#include <iostream>
#include <vector>

using namespace std;

const int mod = 10000;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int a0, a1, p, q, k;
    while(cin >> a0 >> a1 >> p >> q >> k){
        if(k == 0){
            cout << a0 << "\n";
            continue;
        }
        if(k == 1){
            cout << a1 << "\n";
            continue;
        }
        vector<int> vec(k + 1, 0);
        vec[0] = a0;
        vec[1] = a1;
        for(int i = 2; i <= k; i++){
            int m = (vec[i - 1] * p) % mod;
            int n = (vec[i - 2] * q) % mod;
            vec[i] = (m + n) % mod;
        }
        cout << vec[k] << "\n";
    }
    return 0;
}