Submission #1289197

#	Time	Username	Problem	Language	Result	Execution time	Memory
1289197		daffuwu	Star Trek (CEOI20_startrek)	C++20	0 / 100	1 ms	572 KiB

startrek

#include <bits/stdc++.h>
using namespace std;
#define fr first
#define sc second
//startrek

int n, u, v, ans;
long long d;
const int dv = 1e9+7;

int fe(int x, long long y)
{
    int res = 1;
    for (; y>0; y/=2)
    {
        if (y%2==1) res = 1ll*res*x%dv;
        x = 1ll*x*x%dv; 
    }
    return res;
}

int main()
{
    int i;
    scanf("%d%lld", &n, &d);
    for (i=1; i<=n-1; i++)
    {
        scanf("%d%d", &u, &v);
    }
    printf("%d\n", fe(2, d));
}

Compilation message (stderr)

startrek.cpp: In function 'int main()':
startrek.cpp:25:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |     scanf("%d%lld", &n, &d);
      |     ~~~~~^~~~~~~~~~~~~~~~~~
startrek.cpp:28:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |         scanf("%d%d", &u, &v);
      |         ~~~~~^~~~~~~~~~~~~~~~

• 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