Submission #606109

#	Time	Username	Problem	Language	Result	Execution time	Memory
606109		jjiangly	Bank (IZhO14_bank)	C++14	44 / 100	1088 ms	316 KiB

bank

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

#define all(x) x.begin(), x.end()
#define siz(x) int(x.size())
#define ll long long
#define ar array
#define vt vector
#define inf INT_MAX
#define lnf LLONG_MAX

const int nxm = int(2e5) + 7;
int n, m, a[25], b[25];

namespace sub1 {
  void exe() {
    bool ok = false;
    function<void(int, int)> work = [&](int idx, int v) {
      if (idx == m) {
        ok = (v == a[0] ? true : ok);
        return;
      }
      work(idx + 1, v + b[idx]);
      work(idx + 1, v);
    };
    work(0, 0);
    cout << (ok ? "YES" : "NO") << "\n";
  }
};

namespace sub2 {
  void exe() {
    vt<int> p(m);
    iota(all(p), 0);
    bool ok = false;
    do {
      int cnt = 0, sum = 0;
      for (int i = 0; i < m; ++i) {
        sum += b[p[i]];
        if (sum == a[cnt]) {
          ++cnt;
          sum = 0;
        }
        if (cnt >= n) {
          break;
        }
      }
      if (cnt == n) {
        ok = true;
      }
    } while (next_permutation(all(p)));
    cout << (ok ? "YES" : "NO") << "\n";
  }
};

namespace sub3 {
  void exe() {
    vt<vt<int>> f(n);
    for (int i = 0; i < n; ++i) {
      function<void(int, int, int)> work = [&](int idx, int v, int mask) {
        if (idx == m) {
          if (v == a[i]) {
            f[i].push_back(mask);
          }
          return;
        }
        work(idx + 1, v + b[idx], mask | (1 << idx));
        work(idx + 1, v, mask);
      };
      work(0, 0, 0);
    }
    vt<vt<bool>> dp(n, vt<bool> ((1 << m), false));
    for (int i = 1; i < n; ++i) {
      for (int mask = 0; mask < (1 << m); ++mask) {
        if (dp[i - 1][mask]) {
          for (int v : f[i]) {
            if (mask | v == mask) {
              dp[i][mask ^ v] = true;
            }
          }
        }
      }
    }
    bool ok = false;
    for (int mask = 0; mask < (1 << m); ++mask) {
      if (dp[n - 1][mask]) {
        ok = true;
      }
    }
    cout << (ok ? "YES" : "NO") << "\n";
  }
};

int subtask() {
  if (n == 1) {
    return 1;
  } else if (n <= 10) {
    return 2;
  } else if (n <= 20 && m <= 14) {
    return 3;
  }
  return 4;
}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  cin >> n >> m;
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
  }
  for (int i = 0; i < m; ++i) {
    cin >> b[i];
  }
  if (n > m) {
    cout << "NO\n";
  }
  if (subtask() == 1) {
    sub1::exe();
  } else if (subtask() == 2) {
    sub2::exe();
  } else if (subtask() == 3) {
    sub3::exe();
  }

  return 0;
}

Compilation message (stderr)

bank.cpp: In function 'void sub3::exe()':
bank.cpp:77:26: warning: suggest parentheses around comparison in operand of '|' [-Wparentheses]
   77 |             if (mask | v == mask) {
      |                        ~~^~~~~~~

• Subtask 1: 19 / 19
• Subtask 2: 25 / 25
• Subtask 3: 0 / 27
• Subtask 4: 0 / 29