Submission #588780

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
588780	2022-07-04T04:39:47 Z	jiahng	Star Trek (CEOI20_startrek)	C++14	23 / 100	1000 ms	20784 KB

startrek

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
#define int ll
typedef pair<int32_t, int32_t> pi;
typedef vector <int> vi;
typedef vector <pi> vpi;
typedef pair<pi, ll> pii;
typedef set <ll> si;
typedef long double ld;
#define f first
#define s second
#define mp make_pair
#define FOR(i,s,e) for(int i=s;i<=int(e);++i)
#define DEC(i,s,e) for(int i=s;i>=int(e);--i)
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define lbd(x, y) lower_bound(all(x), y)
#define ubd(x, y) upper_bound(all(x), y)
#define aFOR(i,x) for (auto i: x)
#define mem(x,i) memset(x,i,sizeof x)
#define fast ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0)
#define maxn 400010
#define INF (ll)(1e9+10)
#define MOD 1000000007
typedef pair <vi, int> pvi;
typedef pair <int,pi> ipi;
typedef vector <pii> vpii;
typedef pair <pi,pi> pipi;

int N,D,a,b;
vi adj[maxn];

bool win[maxn];
int firstpar[maxn], depth[maxn];

void dfs(int x, int p){
	win[x] = 0;
	aFOR(i,adj[x]) if (i != p){
		depth[i] = depth[x] + 1; dfs(i,x);
		win[x] |= !win[i];
	}
}

void dfs2(int x,int p){
	if (p == -1) firstpar[x] = x;
	else{
		firstpar[x] = firstpar[p];
		aFOR(i, adj[p]) if (depth[i] == depth[x] && i != x && !win[i]){
			firstpar[x] = x;
		}
	}
	aFOR(i,adj[x]) if (i != p) dfs2(i,x);
}

int qexp(int a,int b){
	int ans = 1;
	while (b){
		if (b & 1) (ans *= a) %= MOD;
		(a *= a) %= MOD;
		b <<= 1;
	}
	return ans;
}
int32_t main(){
    fast;
    cin >> N >> D;
    FOR(i,1,N-1){
		cin >> a >> b; adj[a].pb(b); adj[b].pb(a);
	}
	
	int numnexte = 0,numnexto = 0, numwin = 0;
	
	int ans = 0;
	FOR(i,1,N){
		depth[i] = 0; dfs(i,-1); dfs2(i,-1);
		ans += win[i];
		int nnexte = 0,nnexto = 0, nwin = 0;
		FOR(j,1,N){
			if (win[j]) nwin++;
			else if (firstpar[j] == i){
				if (depth[1] % 2 == 0) nnexte++;
				else nnexto++;
			}else if ((depth[j] - depth[firstpar[j]]) % 2 == 1) nwin++;
		}
		numnexte += nnexte; numnexto += nnexto; numwin += nwin;
	}
	
	
	//~ cout << ans << '\n';
	DEC(j,D-1,1) ans = (numnexto - numnexte) * ans + N * numwin + qexp(N, 2*(D-j)-1) * numnexte;
	//~ cout << (nnexto1 - nnexte1) * ans + nwin1 * N + qexp(N, 2*D-1)* nnexte1;
	int x = ans; ans = 0;
	FOR(i,1,N){
		depth[i] = 0; dfs(i,-1); dfs2(i,-1);
		if (win[1]) (ans += N) %= MOD;
		else if (firstpar[1] == i){
			if (depth[1] % 2 == 0) (ans += N - x) %= MOD;
			else (ans += x) %= MOD;
		}else if ((depth[1] - depth[firstpar[1]]) % 2 == 1) (ans += N) %= MOD;
		
	}
	cout << ans;
}

Subtask #1
0.0 / 0.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	6 ms	9716 KB	Output is correct
2	Incorrect	97 ms	9780 KB	Output isn't correct
3	Halted	0 ms	0 KB	-

Subtask #2
0 / 7.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	7 ms	9684 KB	Output isn't correct
2	Halted	0 ms	0 KB	-

Subtask #3
8.0 / 8.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	9684 KB	Output is correct
2	Correct	6 ms	9684 KB	Output is correct
3	Correct	6 ms	9724 KB	Output is correct
4	Correct	6 ms	9684 KB	Output is correct
5	Correct	7 ms	9716 KB	Output is correct
6	Correct	6 ms	9684 KB	Output is correct

Subtask #4
15.0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	9684 KB	Output is correct
2	Correct	6 ms	9684 KB	Output is correct
3	Correct	6 ms	9724 KB	Output is correct
4	Correct	6 ms	9684 KB	Output is correct
5	Correct	7 ms	9716 KB	Output is correct
6	Correct	6 ms	9684 KB	Output is correct
7	Correct	79 ms	9808 KB	Output is correct
8	Correct	89 ms	9848 KB	Output is correct
9	Correct	606 ms	9684 KB	Output is correct
10	Correct	90 ms	9776 KB	Output is correct
11	Correct	98 ms	9784 KB	Output is correct

Subtask #5
0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	9684 KB	Output is correct
2	Correct	6 ms	9684 KB	Output is correct
3	Correct	6 ms	9724 KB	Output is correct
4	Correct	6 ms	9684 KB	Output is correct
5	Correct	7 ms	9716 KB	Output is correct
6	Correct	6 ms	9684 KB	Output is correct
7	Correct	79 ms	9808 KB	Output is correct
8	Correct	89 ms	9848 KB	Output is correct
9	Correct	606 ms	9684 KB	Output is correct
10	Correct	90 ms	9776 KB	Output is correct
11	Correct	98 ms	9784 KB	Output is correct
12	Execution timed out	1056 ms	20784 KB	Time limit exceeded
13	Halted	0 ms	0 KB	-

Subtask #6
0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	9684 KB	Output is correct
2	Correct	6 ms	9684 KB	Output is correct
3	Correct	6 ms	9724 KB	Output is correct
4	Correct	6 ms	9684 KB	Output is correct
5	Correct	7 ms	9716 KB	Output is correct
6	Correct	6 ms	9684 KB	Output is correct
7	Correct	79 ms	9808 KB	Output is correct
8	Correct	89 ms	9848 KB	Output is correct
9	Correct	606 ms	9684 KB	Output is correct
10	Correct	90 ms	9776 KB	Output is correct
11	Correct	98 ms	9784 KB	Output is correct
12	Correct	7 ms	9736 KB	Output is correct
13	Incorrect	101 ms	9780 KB	Output isn't correct
14	Halted	0 ms	0 KB	-

Subtask #7
0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	9684 KB	Output is correct
2	Correct	6 ms	9684 KB	Output is correct
3	Correct	6 ms	9724 KB	Output is correct
4	Correct	6 ms	9684 KB	Output is correct
5	Correct	7 ms	9716 KB	Output is correct
6	Correct	6 ms	9684 KB	Output is correct
7	Correct	79 ms	9808 KB	Output is correct
8	Correct	89 ms	9848 KB	Output is correct
9	Correct	606 ms	9684 KB	Output is correct
10	Correct	90 ms	9776 KB	Output is correct
11	Correct	98 ms	9784 KB	Output is correct
12	Execution timed out	1056 ms	20784 KB	Time limit exceeded
13	Halted	0 ms	0 KB	-

Subtask #8
0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	6 ms	9716 KB	Output is correct
2	Incorrect	97 ms	9780 KB	Output isn't correct
3	Halted	0 ms	0 KB	-

Submission #588780

Compilation message