Submission #1121617

#	Time	Username	Problem	Language	Result	Execution time	Memory
1121617		vjudge1	Ice Hockey World Championship (CEOI15_bobek)	C++17	100 / 100	386 ms	8764 KiB

bobek

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define run  ios_base::sync_with_stdio(false);cin.tie(0);
 
#define ll long long
#define pll pair<ll, ll>
#define ull unsigned ll
#define ld double
#define endl "\n"
#define pb push_back
#define fi first
#define se second
 
#define pi acos(-1)
#define N 4007
#define minimum -9223372036854775807
#define maximum -minimum
#define mod 1000000007
 
using namespace std;
using namespace __gnu_pbds;
template <class t>
using ordered_set=tree<t, null_type,less_equal<t>, rb_tree_tag,tree_order_statistics_node_update>;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

ll gcd(ll a, ll b)
{
	if(b==0)
		return a;
	return gcd(b, a%b);
}

ll lcm(ll a, ll b)
{
	return a/gcd(a, b)*b;
}

bool isprime(ll n)
{
	if(n==1)
		return 0;
	for(ll i=2; i*i<=n; i++)
	{
		if(n%i==0)
			return 0;
	}
	return 1;
}

ll binpow(ll a, ll b)
{
    a%=mod;
    ll res=1;
    while(b>0)
	{
        if(b%2==1)
            res=(res*a)%mod;
        a=(a*a)%mod;
        b/=2;
    }
    return res;
}

int main()
{
	run;
	ll n, k;
	cin>>n>>k;
	ll a[n];
	for(ll i=0; i<n; i++)
	{
		cin>>a[i];
	}
	vector<ll>v;
	ll sm=0, say=n/2, say2=n-say;
	for(ll i=0; i<(1<<say); i++)
	{
		sm=0;
		for(ll j=0; j<say; j++)
		{
			if((1<<j)&i)
			{
				sm+=a[j];
			}
		}
		v.pb(sm);
	}
	sort(v.begin(), v.end());
	ll sz=v.size(), cvb=0;
	for(ll i=0; i<(1<<say2); i++)
	{
		sm=0;
		for(ll j=0; j<say2; j++)
		{
			if((1<<j)&i)
			{
				sm+=a[j+say];
			}
		}
//		cout<<sm<<" ";
		ll cur=upper_bound(v.begin(), v.end(), k-sm)-v.begin();
//		cout<<cur<<endl;
		cvb+=cur;
	}
	cout<<cvb<<endl;
}
/*
2
1 1  1
1 2  2

3 
1 1 1  1
1 1 2  2
1 2 1  3
1 2 2  4
1 2 3  5

4
1 1 1 1  1
1 1 1 2  2
1 1 2 1  3
1 1 2 2  4
1 1 2 3  5
1 2 1 1  6
1 2 1 2  7
1 2 2 1  8
1 2 2 2  9
1 2 2 3  10
1 2 3 2  11
1 2 3 3  12
1 2 3 4  13




1 1 1 1 1  1
1 1 1 1 2  2
1 1 1 2 1  3
1 1 1 2 2  4
1 1 1 2 3  5
1 1 2 1 1  6
1 1 2 1 2  7
1 1 2 2 1  8
1 1 2 2 2  9
1 1 2 2 3  10
1 1 2 3 2  11
1 1 2 3 3  12
1 1 2 3 4  13
1 1 3 2 1
1 1 3 2 2
1 1 3 2 3
1 1 3 3 2
1 1 3 3 3
1 1 3 3 4
1 1 3 4 3
1 1 3 4 4
1 1 3 4 5
1 2 1 1 1
*/
// By Xanlar

Compilation message (stderr)

bobek.cpp: In function 'int main()':
bobek.cpp:91:5: warning: unused variable 'sz' [-Wunused-variable]
   91 |  ll sz=v.size(), cvb=0;
      |     ^~

• 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