Submission #681875

#	Time	Username	Problem	Language	Result	Execution time	Memory
681875		Doncho_Bonboncho	San (COCI17_san)	C++14	0 / 120	300 ms	54564 KiB

san

#include <algorithm>
#include <bits/stdc++.h>
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

const int MAX_N = 1e6;
const int INF = 1e9;
const int mod = 1e9 + 7;

int n, k;

std::vector<ll> L[MAX_N];
std::vector<ll> R[MAX_N];

ll h[MAX_N];
ll c[MAX_N];

std::vector<int> hs; 

void left( int pos, int currH, int sum ){
	if( pos == n/2 ){
		int ind = std::lower_bound( hs.begin(), hs.end(), currH ) - hs.begin();
		L[ind].push_back(sum);
		return;
	}

	left( pos +1, currH, sum );
	if( currH <= h[pos] ){
		left( pos +1, h[pos], sum + c[pos] );
	}
}

void right( int pos, int first, int currH, int sum ){
	if( pos == n ){
		int ind = std::lower_bound( hs.begin(), hs.end(), first ) - hs.begin();
		R[ind].push_back( sum );	
		return ;
	}

	right( pos +1, first, currH, sum );
	if( h[pos] >= currH ){
		if( first == 0 ) first = h[pos];
		right( pos +1, first, h[pos], sum + c[pos] );
	}
}

int main () {

	std::ios_base::sync_with_stdio(false); std::cin.tie(NULL);

	std::cin>>n>>k;
	for( int i=0 ; i<n ; i++ ){
		std::cin>>h[i]>>c[i];
		hs.push_back( h[i] );
	}
	hs.push_back(0);
	std::sort( hs.begin(), hs.end() );

	left( 0, 0, 0 );
	right(n/2, 0, 0, 0);
	/*
	std::cerr<<" L:\n";
	for( int i=0 ; i<n ; i++ ){
		std::cerr<<i<<" : ";
		for( auto j : L[i] ){
			std::cerr<<j<<" ";
		}
		std::cerr<<"\n";
	}

	std::cerr<<" R:\n";
	for( int i=0 ; i<n ; i++ ){
		std::cerr<<i<<" : ";
		for( auto j : R[i] ){
			std::cerr<<j<<" ";
		}
		std::cerr<<"\n";
	}
	*/

	for( int i=0 ; i<(int)hs.size() ; i++ ) std::sort( R[i].begin(), R[i].end() );

	ll nas = 0;
	for( int i=0 ; i<(int)hs.size(); i++ ){

	//	std::cerr<<i<<":\n";
		for( auto it : L[i] ){
			nas += R[0].end() - std::lower_bound( R[0].begin(), R[0].end(), k - it );
	//		std::cerr<<"	"<<it<<"\n";
			for( int j=i ; j<(int)hs.size() ; j++ ){
				ll currNas = R[j].end() - std::lower_bound( R[j].begin(), R[j].end(), k-it );
	//			std::cerr<<"	  # "<<j<<" "<<currNas<<"\n";
				nas += currNas;
			}
		}
	}

	std::cout<<nas<<"\n";

	return 0;
}

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• Subtask 3: 0 / 24
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