답안 #557701

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
557701	2022-05-05T20:30:46 Z	status_coding	Star Trek (CEOI20_startrek)	C++14	50 / 100	1000 ms	14748 KB

startrek

#include <bits/stdc++.h>
#define mod 1000000007

using namespace std;

struct nodS
{
    bool dp;
    int nrFChild, nrCrit;
    vector<int> v;
};

long long put(long long baza, long long exp)
{
    if(!exp)
        return 1;

    long long ans = put(baza, exp/2);
    ans *= ans;
    ans %= mod;

    if(exp % 2)
    {
        ans *= baza;
        ans %= mod;
    }

    return ans;
}

long long n,d;

nodS nod[100005];

bool win[100005];
long long nrCrit[100005];

long long dp[100005];

void addChild(int p, int it)
{
    if(!nod[it].dp)
    {
        nod[p].nrFChild ++;
        nod[p].dp = true;
    }
}

void dfs(int p, int par)
{
    nod[p].nrFChild = 0;
    nod[p].nrCrit = 0;

    for(int it : nod[p].v)
    {
        if(it == par)
            continue;

        dfs(it, p);

        addChild(p, it);
    }

    nod[p].dp = (nod[p].nrFChild > 0);

    if(!nod[p].dp)
        nod[p].nrCrit = 1;
    else
        nod[p].nrCrit = 0;

    for(int it : nod[p].v)
    {
        if(it == par)
            continue;

        if(nod[p].dp && !nod[it].dp && nod[p].nrFChild == 1)
            nod[p].nrCrit += nod[it].nrCrit;

        if(!nod[p].dp && nod[it].dp)
            nod[p].nrCrit += nod[it].nrCrit;
    }
}

int main()
{
    cin>>n>>d;

    if(n == 2)
    {
        cout<<put(n, 2*d);
        return 0;
    }

    for(int i=1;i<n;i++)
    {
        int x, y;
        cin>>x>>y;

        nod[x].v.push_back(y);
        nod[y].v.push_back(x);
    }

    for(int i=1;i<=n;i++)
    {
        dfs(i, 0);

        win[i] = nod[i].dp;
        nrCrit[i] = nod[i].nrCrit;
    }

    for(int i=1;i<=n;i++)
    {
        if(!win[i])
            dp[i] = 1;
    }

    for(int i=d-1 ;i>=0; i--)
    {
        long long nrF=0;

        for(int j=1;j<=n;j++)
        {
            nrF += dp[j];
            nrF %= mod;
        }

        long long nrW = put(n, 2*(d-i-1) + 1 ) - nrF + mod;
        nrW %= mod;

        //cout<<nrW<<' '<<nrF<<'\n';

        for(int j=1;j<=n;j++)
        {
            if(!win[j])
            {
                dp[j] = (n - nrCrit[j]) * (nrF + nrW);
                dp[j] %= mod;

                dp[j] += nrCrit[j] * nrW;
                dp[j] %= mod;
            }
            else
            {
                dp[j] = nrCrit[j] * nrF;
                dp[j] %= mod;
            }
        }
    }

    cout<<(put(n, 2*d) - dp[1] + mod) % mod;
    return 0;
}

Subtask #1
0.0 / 0.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	4180 KB	Output is correct
2	Correct	28 ms	4360 KB	Output is correct

Subtask #2
7.0 / 7.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	4180 KB	Output is correct
2	Correct	2 ms	4180 KB	Output is correct
3	Correct	2 ms	4180 KB	Output is correct
4	Correct	2 ms	4180 KB	Output is correct
5	Correct	3 ms	4180 KB	Output is correct

Subtask #3
8.0 / 8.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	4180 KB	Output is correct
2	Correct	2 ms	4180 KB	Output is correct
3	Correct	2 ms	4180 KB	Output is correct
4	Correct	2 ms	4180 KB	Output is correct
5	Correct	3 ms	4180 KB	Output is correct
6	Correct	2 ms	4180 KB	Output is correct

Subtask #4
15.0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	4180 KB	Output is correct
2	Correct	2 ms	4180 KB	Output is correct
3	Correct	2 ms	4180 KB	Output is correct
4	Correct	2 ms	4180 KB	Output is correct
5	Correct	3 ms	4180 KB	Output is correct
6	Correct	2 ms	4180 KB	Output is correct
7	Correct	23 ms	4320 KB	Output is correct
8	Correct	29 ms	4352 KB	Output is correct
9	Correct	17 ms	4264 KB	Output is correct
10	Correct	22 ms	4260 KB	Output is correct
11	Correct	22 ms	4200 KB	Output is correct

Subtask #5
0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	4180 KB	Output is correct
2	Correct	2 ms	4180 KB	Output is correct
3	Correct	2 ms	4180 KB	Output is correct
4	Correct	2 ms	4180 KB	Output is correct
5	Correct	3 ms	4180 KB	Output is correct
6	Correct	2 ms	4180 KB	Output is correct
7	Correct	23 ms	4320 KB	Output is correct
8	Correct	29 ms	4352 KB	Output is correct
9	Correct	17 ms	4264 KB	Output is correct
10	Correct	22 ms	4260 KB	Output is correct
11	Correct	22 ms	4200 KB	Output is correct
12	Execution timed out	1084 ms	14748 KB	Time limit exceeded
13	Halted	0 ms	0 KB	-

Subtask #6
20.0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	4180 KB	Output is correct
2	Correct	2 ms	4180 KB	Output is correct
3	Correct	2 ms	4180 KB	Output is correct
4	Correct	2 ms	4180 KB	Output is correct
5	Correct	3 ms	4180 KB	Output is correct
6	Correct	2 ms	4180 KB	Output is correct
7	Correct	23 ms	4320 KB	Output is correct
8	Correct	29 ms	4352 KB	Output is correct
9	Correct	17 ms	4264 KB	Output is correct
10	Correct	22 ms	4260 KB	Output is correct
11	Correct	22 ms	4200 KB	Output is correct
12	Correct	2 ms	4180 KB	Output is correct
13	Correct	28 ms	4180 KB	Output is correct
14	Correct	2 ms	4180 KB	Output is correct
15	Correct	2 ms	4180 KB	Output is correct
16	Correct	2 ms	4180 KB	Output is correct
17	Correct	3 ms	4216 KB	Output is correct
18	Correct	3 ms	4224 KB	Output is correct
19	Correct	2 ms	4180 KB	Output is correct
20	Correct	2 ms	4180 KB	Output is correct
21	Correct	23 ms	4316 KB	Output is correct
22	Correct	26 ms	4308 KB	Output is correct
23	Correct	18 ms	4272 KB	Output is correct
24	Correct	23 ms	4272 KB	Output is correct
25	Correct	23 ms	4272 KB	Output is correct
26	Correct	546 ms	4224 KB	Output is correct
27	Correct	562 ms	4356 KB	Output is correct
28	Correct	557 ms	4260 KB	Output is correct
29	Correct	545 ms	4264 KB	Output is correct
30	Correct	406 ms	4264 KB	Output is correct

Subtask #7
0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	4180 KB	Output is correct
2	Correct	2 ms	4180 KB	Output is correct
3	Correct	2 ms	4180 KB	Output is correct
4	Correct	2 ms	4180 KB	Output is correct
5	Correct	3 ms	4180 KB	Output is correct
6	Correct	2 ms	4180 KB	Output is correct
7	Correct	23 ms	4320 KB	Output is correct
8	Correct	29 ms	4352 KB	Output is correct
9	Correct	17 ms	4264 KB	Output is correct
10	Correct	22 ms	4260 KB	Output is correct
11	Correct	22 ms	4200 KB	Output is correct
12	Execution timed out	1084 ms	14748 KB	Time limit exceeded
13	Halted	0 ms	0 KB	-

Subtask #8
0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	4180 KB	Output is correct
2	Correct	28 ms	4360 KB	Output is correct
3	Correct	2 ms	4180 KB	Output is correct
4	Correct	2 ms	4180 KB	Output is correct
5	Correct	2 ms	4180 KB	Output is correct
6	Correct	2 ms	4180 KB	Output is correct
7	Correct	3 ms	4180 KB	Output is correct
8	Correct	2 ms	4180 KB	Output is correct
9	Correct	2 ms	4180 KB	Output is correct
10	Correct	2 ms	4180 KB	Output is correct
11	Correct	2 ms	4180 KB	Output is correct
12	Correct	3 ms	4180 KB	Output is correct
13	Correct	2 ms	4180 KB	Output is correct
14	Correct	23 ms	4320 KB	Output is correct
15	Correct	29 ms	4352 KB	Output is correct
16	Correct	17 ms	4264 KB	Output is correct
17	Correct	22 ms	4260 KB	Output is correct
18	Correct	22 ms	4200 KB	Output is correct
19	Execution timed out	1084 ms	14748 KB	Time limit exceeded
20	Halted	0 ms	0 KB	-

답안 #557701

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