제출 #641615

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
641615		Itamar	Star Trek (CEOI20_startrek)	C++14	0 / 100	2 ms	2644 KiB

startrek

using namespace std;
#include <iostream>
#include <vector>
#define pi pair<int,int>
#define vi vector<int>
#define ll long long

vector<vi> f(1e5);
ll m = 1e9 + 7;
ll pow(ll a, ll b) {
    if (b == 0)
        return 1;
    ll ans = pow(a, b / 2);
    ans = (ans * ans) % m;
    if (b % 2) {
        ans = (ans * a) % m;
    }
    return ans;
}
int main()
{
    ll n,d;
    cin >> n >> d;

    for (int i = 0; i < n-1; i++) {
        int a, b;
        cin >> a >> b;
        a--, b--;
        f[a].push_back(b);
        f[b].push_back(a);
    }
    cout << pow(4, d) - 1;
}

• Subtask 1: 0 / 0
• Subtask 2: 0 / 7
• Subtask 3: 0 / 8
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20
• Subtask 8: 0 / 15