Submission #1282571

#	Time	Username	Problem	Language	Result	Execution time	Memory
1282571		Yunan	Bank (IZhO14_bank)	C++20	100 / 100	404 ms	3080 KiB

bank

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

bool ans;
int n, m;
vector<int> a, b;
vector<vector<bool>> memo;
vector<vector<int>> masks;

void DFS(int mask, int i) {
    if (ans) return;
    if (i == n) {
        ans = true;
        return;
    }
    if (memo[i][mask] == false) {
        return;
    }
    for (auto next_mask : masks[i]) {
        if (ans) return;
        if (next_mask & mask) continue;
        DFS(mask | next_mask, i + 1);
        if (ans) return;
    }
    memo[i][mask] = false;
}

void Solve() {
    cin >> n >> m;
    a.resize(n);
    b.resize(m);
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }
    // sort(a.begin(), a.end());
    for (int i = 0; i < m; ++i) {
        cin >> b[i];
    }
    int full_mask = (1 << m) - 1;
    masks.resize(n);
    for (int i = 0; i < n; ++i) {
        for (int mask = 0; mask <= full_mask; ++mask) {
            int sum = 0;
            for (int j = 0; j < m; ++j) {
                sum += b[j] * ((mask >> j) & 1);
            }
            if (sum == a[i]) {
                masks[i].push_back(mask);
            }
        }
    }
    memo.assign(n, vector<bool>(full_mask + 1, true));
    DFS(0, 0);
    cout << (ans ? "YES" : "NO");
}

int main() {
    ios_base :: sync_with_stdio(false); cin.tie(0); cout.tie(0);
    if (fopen("test.inp", "r")) {
        freopen("test.inp", "r", stdin);
        freopen("test.out", "w", stdout);
    }
    Solve();
}

Compilation message (stderr)

bank.cpp: In function 'int main()':
bank.cpp:60:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |         freopen("test.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bank.cpp:61:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   61 |         freopen("test.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 19 / 19
• Subtask 2: 25 / 25
• Subtask 3: 27 / 27
• Subtask 4: 29 / 29