oj.uz

Submission #398903

# Submission time Handle Problem Language Result Execution time Memory
398903 2021-05-04T22:02:53 Z AmineWeslati The Xana coup (BOI21_xanadu) C++14
55 / 100
 133 ms 18660 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<int>vi;
#define pb push_back
#define sz(v) (int)v.size()
#define FOR(i,a,b) for(int i=a; i<b; i++)

void ckmin(int &x, int y){x=min(x,y);}

void IO() {
#ifdef LOCAL
    freopen("input.txt", "r", stdin); 
    freopen("output.txt", "w", stdout);
#endif
}
//------------------------------------------------//

const int MX=1e5+10;
const int INF=1e9;
int N; 
vi adj[MX],a(MX);

int memo[MX][2][2];
int solve(int u, int p, int f, int ff){
	int &ind=memo[u][f][ff];
	if(ind!=-1) return ind; 

	int st=a[u]; if(f) st=1-st; if(ff) st=1-st;

	int ans=INF,n=sz(adj[u])-(u!=1); 
	
	FOR(m,0,((1)<<(n))) if(((__builtin_popcount(m))&1)==st){
		int cur=ff,idx=0;
		for(int v: adj[u]) if(v!=p){
			int nf=(((m)>>(idx))&1);
			cur+=solve(v,u,ff,nf);
			if(cur>INF) cur=INF;
			idx++;
		}
		ckmin(ans,cur);
	}
	
	return ind=ans; 
}

int main(){
	IO();

	cin>>N;
	FOR(i,0,N-1){
		int u,v; cin>>u>>v;
		adj[u].pb(v);
		adj[v].pb(u);
	}
	FOR(i,1,N+1) cin>>a[i];

	memset(memo,-1,sizeof(memo));
	int ans=min(solve(1,1,0,0),solve(1,1,0,1));
	if(ans==INF) cout << "impossible" << endl;
	else cout << ans << endl;

}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4556 KB Output is correct
2 Correct 3 ms 4556 KB Output is correct
3 Correct 3 ms 4556 KB Output is correct
4 Correct 3 ms 4592 KB Output is correct
5 Correct 3 ms 4556 KB Output is correct

Subtask #2
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4556 KB Output is correct
2 Correct 3 ms 4556 KB Output is correct
3 Correct 3 ms 4556 KB Output is correct
4 Correct 3 ms 4592 KB Output is correct
5 Correct 3 ms 4556 KB Output is correct
6 Correct 3 ms 4556 KB Output is correct
7 Correct 3 ms 4556 KB Output is correct
8 Correct 3 ms 4556 KB Output is correct
9 Correct 3 ms 4556 KB Output is correct
10 Correct 3 ms 4556 KB Output is correct
11 Correct 3 ms 4556 KB Output is correct
12 Correct 3 ms 4556 KB Output is correct
13 Correct 3 ms 4556 KB Output is correct
14 Correct 3 ms 4600 KB Output is correct
15 Incorrect 3 ms 4592 KB Output isn't correct
16 Halted 0 ms 0 KB -

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 116 ms 18560 KB Output is correct
2 Correct 119 ms 18372 KB Output is correct
3 Correct 119 ms 18600 KB Output is correct

Subtask #4
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 124 ms 18596 KB Output is correct
2 Correct 118 ms 18428 KB Output is correct
3 Correct 118 ms 18660 KB Output is correct
4 Correct 110 ms 7364 KB Output is correct
5 Correct 131 ms 9044 KB Output is correct
6 Correct 128 ms 9000 KB Output is correct
7 Correct 3 ms 4556 KB Output is correct
8 Correct 40 ms 6060 KB Output is correct
9 Correct 123 ms 9064 KB Output is correct
10 Correct 133 ms 9300 KB Output is correct
11 Correct 123 ms 9796 KB Output is correct
12 Correct 128 ms 10004 KB Output is correct
13 Correct 114 ms 8716 KB Output is correct
14 Correct 125 ms 9072 KB Output is correct

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4556 KB Output is correct
2 Correct 3 ms 4556 KB Output is correct
3 Correct 3 ms 4556 KB Output is correct
4 Correct 3 ms 4592 KB Output is correct
5 Correct 3 ms 4556 KB Output is correct
6 Correct 3 ms 4556 KB Output is correct
7 Correct 3 ms 4556 KB Output is correct
8 Correct 3 ms 4556 KB Output is correct
9 Correct 3 ms 4556 KB Output is correct
10 Correct 3 ms 4556 KB Output is correct
11 Correct 3 ms 4556 KB Output is correct
12 Correct 3 ms 4556 KB Output is correct
13 Correct 3 ms 4556 KB Output is correct
14 Correct 3 ms 4600 KB Output is correct
15 Incorrect 3 ms 4592 KB Output isn't correct
16 Halted 0 ms 0 KB -