Submission #1085767

#	Time	Username	Problem	Language	Result	Execution time	Memory
1085767		juicy	Ice Hockey World Championship (CEOI15_bobek)	C++17	100 / 100	303 ms	20916 KiB

bobek

#include <bits/stdc++.h>
 
using namespace std;
 
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif
 
int main() {
  ios::sync_with_stdio(false); cin.tie(nullptr);
 
  int n; long long k; cin >> n >> k;
  vector<long long> a(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
  }
  vector<long long> lt, rt;
  for (int m = 0; m < (1 << n / 2); ++m) {
    long long sum = 0;
    for (int i = 0; i < n / 2; ++i) {
      if (m >> i & 1) {
        sum += a[i];
      }
    }
    lt.push_back(sum);
  }
  for (int m = 0; m < (1 << n - n / 2); ++m) {
    long long sum = 0;
    for (int i = 0; i < n - n / 2; ++i) {
      if (m >> i & 1) {
        sum += a[n / 2 + i];
      }
    }
    rt.push_back(sum);
  }
  sort(lt.rbegin(), lt.rend());
  sort(rt.begin(), rt.end());
  int j = 0;
  long long res = 0;
  for (auto x : lt) {
    while (j < rt.size() && rt[j] + x <= k) {
      ++j;
    }
    res += j;
  }
  cout << res;
  return 0;
}

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.cpp:29:31: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   29 |   for (int m = 0; m < (1 << n - n / 2); ++m) {
      |                             ~~^~~~~~~
bobek.cpp:43:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |     while (j < rt.size() && rt[j] + x <= k) {
      |            ~~^~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10