a62_q1b_chocolate.cpp

#include <bits/stdc++.h>
using namespace std;

int main() {
    std::ios_base::sync_with_stdio(false);std::cin.tie(0);
    int n, k;std::cin >> n >> k;
    vector<int> val(k+1);
    for (int i = 1; i <= k; i++) {
        std::cin >> val[i];
    }
    
    vector<int> dp(n+1, 0);
    dp[0] = 1;
    for (int i = 1; i <= n; i++) {
        for (auto &e: val) {
            if (e <= i) {
                dp[i] = (dp[i] + dp[i - e] % 1000003) % 1000003;
            }
        }
    }
    std::cout << dp[n] << "\n";
    return 0;
}