Submission #46929

#	Time	Username	Problem	Language	Result	Execution time	Memory
46929		alex99	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	371 ms	17568 KiB

bobek

#include <iostream>
#include <algorithm>
using namespace std;
int N;
long long M;
long long A[(1 << 21) + 5], B[(1<< 21) + 5];
long long C[45];
void Read()
{
    cin >> N >> M;
    for(int i = 1; i <= N; i++)
    {
        cin >> C[i];
    }
}

void precalcAB()
{
    int lim = N / 2;
    for(int conf = 0; conf < (1 << lim); conf++)
    {
        long long sum = 0;
        for(int j = 0; j < lim; j++)
        {
            if((conf & (1 << j)) != 0)
                sum += C[j + 1];
        }
        A[conf] = sum;
    }
    for(int conf = 0; conf < (1 << (N - lim)); conf++)
    {
        long long sum = 0;
        for(int j = 0; j < N - lim; j++)
        {
            if((conf & (1 << j)) != 0)
                sum += C[j + lim + 1];
        }
        B[conf] = sum;
    }
    int x = (1 << lim);
    int y = ((1 << (N - lim)));
    sort(A, A + (1 << lim));
    sort(B , B + (1 << (N - lim)));
    int point = 0, point2 = y - 1;
    long long ans = 0;
    for(int i = 0; i < x; i++)
    {
        while(point2 >= 0 && B[point2] + A[i] > M)
            --point2;
        ans += point2 + 1;
    }
    cout << ans << '\n';
}
int main()
{
    Read();
    precalcAB();
    return 0;
}

Compilation message (stderr)

bobek.cpp: In function 'void precalcAB()':
bobek.cpp:44:9: warning: unused variable 'point' [-Wunused-variable]
     int point = 0, point2 = y - 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