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답안 #588770

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
588770 2022-07-04T04:23:07 Z jiahng Star Trek (CEOI20_startrek) C++14
0 / 100
 49 ms 9716 KB 
#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 nnexte1=0,nnexto1=0, nwin1=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 ((depth[j] - depth[firstpar[j]]) % 2 == 1 || win[j]){
				//~ cout << "NWIN " << j << '\n';
				nwin++;
				if (j == 1) nwin1++;
			}else if (firstpar[j] == i){
				if (depth[j]%2 == 0){
					//~ cout << "NNEXTE " << j << '\n';
					nnexte++;
					if (j == 1) nnexte1++;
				}else{
					nnexto++;
					if (j == 1) nnexto1++;
					//~ cout << "NNEXTO " << j << '\n';
				}
			}
		}
		//~ if (i == 1){
			//~ nnexte1 = nnexte; nnexto1 = nnexto;
			//~ nwin1 = nwin;
		//~ }
		//~ return 0;
		//~ cout << nnexto << ' ' << nnexte << ' ' << nwin << '\n';
		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;
}

Subtask #1
0.0 / 0.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Incorrect 49 ms 9684 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 6 ms 9684 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 8.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 9684 KB Output is correct
2 Incorrect 5 ms 9716 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 9684 KB Output is correct
2 Incorrect 5 ms 9716 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #5
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 9684 KB Output is correct
2 Incorrect 5 ms 9716 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #6
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 9684 KB Output is correct
2 Incorrect 5 ms 9716 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #7
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 9684 KB Output is correct
2 Incorrect 5 ms 9716 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #8
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Incorrect 49 ms 9684 KB Output isn't correct
3 Halted 0 ms 0 KB -