Submission #630804

#	Time	Username	Problem	Language	Result	Execution time	Memory
630804		Do_you_copy	Ice Hockey World Championship (CEOI15_bobek)	C++17	100 / 100	229 ms	16744 KiB

bobek

#include <bits/stdc++.h>
//#define int long long
#define fi first
#define se second
#define pb push_back
#define faster ios_base::sync_with_stdio(0); cin.tie(0);
using namespace std;
using ll = long long;
using ull = unsigned ll;
using ld = long double;
using pii = pair <int, int>;
using pil = pair <int, ll>;
using pli = pair <ll, int>;
using pll = pair <ll, ll>;
mt19937 Rand(chrono::steady_clock::now().time_since_epoch().count());

ll min(const ll &a, const ll &b){
    return (a < b) ? a : b;
}

ll max(const ll &a, const ll &b){
    return (a > b) ? a : b;
}

//const ll Mod = 1000000007;
//const ll Mod2 = 999999999989;
//only use when required
const int maxN = 40 + 1;
int n;
ll B;
ll a[maxN];
ll l[1 << 21];
ll r[1 << 21];

void Init(){
    cin >> n >> B;
    for (int i = 1; i <= n; ++i){
        cin >> a[i];
    }
    int k = n / 2;
    for (int mask = 1; mask < 1 << k; ++mask){
        l[mask] = l[mask - (mask & -mask)] + a[__lg(mask & -mask) + 1];
    }
    for (int mask = 1; mask < 1 << (n - k); ++mask){
        r[mask] = r[mask - (mask & -mask)] + a[__lg(mask & -mask) + k + 1];
    }
    sort(l, l + (1 << k));
    sort(r, r + (1 << (n - k)));
    ll ans = 0;
    for (int i = 0; i < 1 << k; ++i){
        int j = upper_bound(r, r + (1 << (n - k)), B - l[i]) - r;
        ans += j;
    }
    cout << ans;
}

#define debu
#define taskname "test"
signed main(){
    if (fopen(taskname".inp", "r")){
        freopen(taskname".inp", "r", stdin);
        #ifdef debug
        freopen(taskname".out", "w", stdout);
        #endif
    }
    faster;
    ll tt = 1;
    //cin >> tt;
    while (tt--){
        Init();
    }
    if (fopen("timeout.txt", "r")){
        ofstream timeout("timeout.txt");
        timeout << 1000 * double(clock()) / CLOCKS_PER_SEC;
        #ifndef debug
        cerr << "\nTime elapsed: " << 1000 * double(clock()) / CLOCKS_PER_SEC << "ms\n";
        #endif
    }
}

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.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(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• 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