Submission #221858

#	Time	Username	Problem	Language	Result	Execution time	Memory
221858		PeppaPig	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	541 ms	20820 KiB

bobek

#include <bits/stdc++.h>

#define long long long

using namespace std;

vector<long> process(vector<long> &v) {
    vector<long> ret;
    for(int i = 0; i < (1 << (int)v.size()); i++) {
        long now = 0;
        for(int j = 0; j < v.size(); j++) if(i >> j & 1)
            now += v[j];
        ret.emplace_back(now);
    }
    return ret;
}

int n;
long m;

int main() {
    scanf("%d %lld", &n, &m);
    vector<long> l, r;
    long a;
    for(int i = 1; i <= n / 2; i++) {
        scanf("%lld", &a);
        l.emplace_back(a);
    }
    for(int i = n / 2 + 1; i <= n; i++) {
        scanf("%lld", &a);
        r.emplace_back(a);
    }
    vector<long> sum_l = process(l);
    vector<long> sum_r = process(r);
    sort(sum_l.begin(), sum_l.end());

    long ans = 0;
    for(long x : sum_r)
        ans += upper_bound(sum_l.begin(), sum_l.end(), m - x) - sum_l.begin();
    printf("%lld\n", ans);

    return 0;
}

Compilation message (stderr)

bobek.cpp: In function 'std::vector<long long int> process(std::vector<long long int>&)':
bobek.cpp:11:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < v.size(); j++) if(i >> j & 1)
                        ~~^~~~~~~~~~
bobek.cpp: In function 'int main()':
bobek.cpp:22:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %lld", &n, &m);
     ~~~~~^~~~~~~~~~~~~~~~~~~
bobek.cpp:26:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld", &a);
         ~~~~~^~~~~~~~~~~~
bobek.cpp:30:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld", &a);
         ~~~~~^~~~~~~~~~~~

• 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