Submission #298582

#	Time	Username	Problem	Language	Result	Execution time	Memory
298582		BeanZ	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	561 ms	8688 KiB

bobek

#include <bits/stdc++.h>

using namespace std;

#define ll long long
#define endl '\n'
const int N = 2e5 + 5;
ll a[N];
map<ll, ll> mem;
int main(){
        ios_base::sync_with_stdio(false);
        cin.tie(0);
        if (fopen("A.INP", "r")){
                freopen("A.INP", "r", stdin);
                freopen("A.OUT", "w", stdout);
        }
        ll n, k;
        cin >> n >> k;
        for (int i = 0; i < n; i++) cin >> a[i];
        ll mid = n / 2;
        ll rem = n - n / 2;
        vector<ll> val;
        for (int i = 0; i < (1 << mid); i++){
                ll sum = 0;
                for (int j = 0; j < mid; j++){
                        if (i & (1 << j)){
                                sum = sum + a[j];
                        }
                }
                val.push_back(sum);
        }
        sort(val.begin(), val.end());
        ll ans = 0;
        for (int i = 0; i < (1 << rem); i++){
                ll sum = 0;
                for (int j = 0; j < rem; j++){
                        if (i & (1 << j)){
                                sum = sum + a[mid + j];
                        }
                }
                if (sum > k) continue;
                ll l = 0, h = val.size() - 1;
                ll res = k - sum;
                while (l <= h){
                        ll mid = (l + h) >> 1;
                        if (val[mid] > res) h = mid - 1;
                        else l = mid + 1;
                }
                if (h >= 0) ans = ans + h + 1;
        }
        cout << ans;
}
/*
*/

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.cpp:14:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   14 |                 freopen("A.INP", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
bobek.cpp:15:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   15 |                 freopen("A.OUT", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• 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