oj.uz

답안 #632477

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
632477 2022-08-20T07:17:13 Z codr0 Sumtree (INOI20_sumtree) C++14
10 / 100
 51 ms 10984 KB 
#include <bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
#define pll pair<ll,ll>

#define F first
#define S second
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORR(i,a,b) for(int i=a;i>=b;i--)
#define err(x) cerr<<#x<<"="<<x<<'\n'
#define lc 2*id
#define rc 2*id+1
#define dmid int mid=(r+l)/2
#define all(x) x.begin(),x.end()
#define SZ(x) (int)x.size()
#define pb push_back
#define maxm(a,b) a=max(a,b)
#define minm(a,b) a=min(a,b)
#define bit(i,j) ((j>>i)&1)

using namespace std;
const int md=1e9+7;
const int N=5e5+4;
int fct[N],inv[N];

	int pw(int a,int b){
		int rt=1;
		while(b){
			if(b&1) rt=1LL*rt*a%md;
			a=1LL*a*a%md;
			b/=2;
		}
		return rt;
	}

	int C(int r,int n){
		return (1LL*(1LL*fct[n]*inv[r]%md)*inv[n-r]%md);
	}

	int32_t main(){
	iostream::sync_with_stdio(0); cin.tie(0);
	
	fct[0]=1; FOR(i,1,N-1) fct[i]=1LL*fct[i-1]*i%md;
	inv[N-1]=pw(fct[N-1],md-2); FORR(i,N-2,0) inv[i]=1LL*inv[i+1]*(i+1)%md;
	int n,r; cin>>n>>r;
	FOR(i,1,n-1){
		int u,v; cin>>u>>v;
	}
	int q; cin>>q;
	assert(q==0);
	cout<<C(n-1,n-1+r)<<'\n';

	return 0;
	}

Subtask #1
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 40 ms 6628 KB Output is correct
2 Correct 40 ms 6632 KB Output is correct
3 Correct 42 ms 6632 KB Output is correct
4 Correct 40 ms 6640 KB Output is correct
5 Correct 45 ms 6628 KB Output is correct
6 Correct 10 ms 4180 KB Output is correct
7 Correct 10 ms 4248 KB Output is correct
8 Correct 10 ms 4152 KB Output is correct
9 Correct 40 ms 6632 KB Output is correct
10 Correct 41 ms 6528 KB Output is correct
11 Correct 51 ms 6636 KB Output is correct
12 Correct 38 ms 6388 KB Output is correct
13 Correct 38 ms 6372 KB Output is correct

Subtask #2
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 12 ms 8336 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #3
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 49 ms 10868 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 49 ms 10984 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 40 ms 6628 KB Output is correct
2 Correct 40 ms 6632 KB Output is correct
3 Correct 42 ms 6632 KB Output is correct
4 Correct 40 ms 6640 KB Output is correct
5 Correct 45 ms 6628 KB Output is correct
6 Correct 10 ms 4180 KB Output is correct
7 Correct 10 ms 4248 KB Output is correct
8 Correct 10 ms 4152 KB Output is correct
9 Correct 40 ms 6632 KB Output is correct
10 Correct 41 ms 6528 KB Output is correct
11 Correct 51 ms 6636 KB Output is correct
12 Correct 38 ms 6388 KB Output is correct
13 Correct 38 ms 6372 KB Output is correct
14 Runtime error 12 ms 8336 KB Execution killed with signal 6
15 Halted 0 ms 0 KB -