Submission #93703

#	Time	Username	Problem	Language	Result	Execution time	Memory
93703		KLPP	Paths (BOI18_paths)	C++14	100 / 100	795 ms	113796 KiB

paths

#include<bits/stdc++.h>

using namespace std;
typedef long long int lld;
int n,m,k;
vector<int> nei[1000000];
int color[1000000];
lld DP[1000000][32];
lld compute(int pos, int msk){
	if(DP[pos][msk]!=-1)return DP[pos][msk];
	int c=color[pos];
	int Bit=msk&(1<<c);
	if(Bit==0){
		DP[pos][msk]=0;
		return 0;
	}
	DP[pos][msk]=0;
	for(int i=0;i<nei[pos].size();i++){
		DP[pos][msk]+=compute(nei[pos][i],msk-(1<<c));
	}
	return DP[pos][msk];
}
int main(){
	cin>>n>>m>>k;
	for(int i=0;i<n;i++){
		cin>>color[i];
		color[i]--;
	}
	for(int i=0;i<m;i++){
		int x,y;
		cin>>x>>y;
		x--;
		y--;
		nei[x].push_back(y);
		nei[y].push_back(x);
	}
	for(int i=0;i<n;i++){
		for(int msk=0;msk<32;msk++)DP[i][msk]=-1;
		DP[i][(1<<color[i])]=1;
	}
	lld ans=0;
	for(int i=0;i<n;i++){
		for(int msk=1;msk<(1<<k);msk++){ans+=compute(i,msk);
			//cout<<compute(i,msk)<<" ";
		}//cout<<endl;
	}
	ans-=n;
	cout<<ans<<endl;
	return 0;
}

Compilation message (stderr)

paths.cpp: In function 'lld compute(int, int)':
paths.cpp:18:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<nei[pos].size();i++){
              ~^~~~~~~~~~~~~~~~

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 27 / 27
• Subtask 4: 30 / 30