Submission #43504

#	Time	Username	Problem	Language	Result	Execution time	Memory
43504		Hassoony	Ice Hockey World Championship (CEOI15_bobek)	C++14	100 / 100	623 ms	33888 KiB

bobek

#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
const int MX=42;
ll n,m,a[MX];
vector<ll>v1,v2;
void calc(int x,ll sum,int fin){
    if(x==fin){
        v1.push_back(sum);
        return;
    }
    calc(x+1,sum+a[x],fin);
    calc(x+1,sum,fin);
}
ll DP(ll x,ll sum){
    if(x==n){
        if(sum<=m)return 1;
        return 0;
    }
    ll ret=DP(x+1,sum);
    ret+=DP(x+1,sum+a[x]);
    return ret;
}
int main(){
    scanf("%lld%lld",&n,&m);
    for(int i=0;i<n;i++){
        scanf("%lld",&a[i]);
    }
    calc(0,0,n/2+1);
    v2=v1;v1.clear();
    calc(n/2+1,0,n);
    ll ans=0;
    sort(v1.begin(),v1.end());
    for(auto pp:v2){
        if(!pp)continue;
        ll idx=upper_bound(v1.begin(),v1.end(),m-pp)-v1.begin();
        ans+=idx;
  //      cout<<pp<<" "<<m-pp<<" "<<idx<<endl;
    }
    for(auto pp:v1)ans+=(pp<=m);
    cout<<ans<<endl;
}

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.cpp:26:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lld%lld",&n,&m);
                            ^
bobek.cpp:28:28: 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