Submission #66064

#	Time	Username	Problem	Language	Result	Execution time	Memory
66064		bazsi700	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	888 ms	9180 KiB

bobek

#include <bits/stdc++.h>

using namespace std;
#define ll long long

//14:20
int n;
ll m;
ll c[45];
ll way[2150000];
unordered_map<ll,int> compr;
vector<ll> did;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m;
    for(int i = 0; i < n; i++) {
        cin >> c[i];
    }
    if(n <= 22) {
        ll ways = 0;
        for(int mask = 0; mask < (1<<n); mask++) {
            ll money = m;
            for(int i = 0; i < n; i++) {
                if(mask&(1<<i)) {
                    money-= c[i];
                }
            }
            if(money >= 0) {
                ways++;
            }
        }
        cout << ways;
    } else {
        ll ways = 0;
        int b1 = 19;
        for(int mask = 0; mask < (1<<b1); mask++) {
            ll money = m;
            for(int i = 0; i < b1; i++) {
                if(mask&(1<<i)) {
                    money-= c[i];
                }
            }
            if(money >= 0) {
                did.push_back(m-money);
            }
        }
        sort(did.begin(),did.end());
        int in = 0;
        ll prev = -1;
        for(ll el : did) {
            way[in++]++;
            prev = el;
        }
        for(int i = 0; i <= in; i++) {
            way[i]+=way[i-1];
        }
        for(int mask = 0; mask < (1<<(n-b1)); mask++) {
            ll money = m;
            for(int i = b1; i < n; i++) {
                if(mask&(1<<(i-b1))) {
                    money-= c[i];
                }
            }
            if(money >= 0) {
                auto it = upper_bound(did.begin(),did.end(),money);
                if(it != did.begin()) {
                    ways+= way[it-did.begin()-1];
                }
            }
        }
        cout << ways;
    }
    return 0;
}

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.cpp:51:12: warning: variable 'prev' set but not used [-Wunused-but-set-variable]
         ll prev = -1;
            ^~~~

• 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