Submission #101761

#	Time	Username	Problem	Language	Result	Execution time	Memory
101761		rocketninja7	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	234 ms	16860 KiB

bobek

#include <cstdio>
#include <algorithm>
using namespace std;
int main(){
    int N;
    long long int M;
    scanf("%d%lld", &N, &M);
    long long int A[N];
    for(int i=0;i<N;i++){
        scanf("%lld", &A[i]);
    }
    long long int sums1[1<<(N/2)];
    for(int i=0;i<(1<<(N/2));i++){
        sums1[i]=1000000000000000001;
        long long int temp=0;
        long long int tempI=i;
        while(tempI>0){
            temp+=A[__builtin_ctz(tempI)];
            if(temp>M){
                break;
            }
            tempI-=tempI&-tempI;
        }
        if(temp<=M){
            sums1[i]=temp;
        }
    }
    long long int sums2[1<<(N-N/2)];
    for(int i=0;i<(1<<(N-N/2));i++){
        sums2[i]=1000000000000000001;
        long long int temp=0;
        long long int tempI=i;
        while(tempI>0){
            temp+=A[__builtin_ctz(tempI)+N/2];
            if(temp>M){
                break;
            }
            tempI-=tempI&-tempI;
        }
        if(temp<=M){
            sums2[i]=temp;
        }
    }
    sort(sums1, sums1+(1<<(N/2)));
    sort(sums2, sums2+(1<<(N-N/2)));
    long long int ans=0;
    int ri=(1<<(N-N/2))-1;
    for(int i=0;i<(1<<(N/2));i++){
        while(ri>-1&&sums1[i]+sums2[ri]>M){
            ri--;
        }
        ans+=ri+1;
    }
    printf("%lld", ans);
    return 0;
}

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.cpp:7:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%lld", &N, &M);
     ~~~~~^~~~~~~~~~~~~~~~~~
bobek.cpp:10:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld", &A[i]);
         ~~~~~^~~~~~~~~~~~~~~

• 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