Submission #19772

#	Time	Username	Problem	Language	Result	Execution time	Memory
19772		myungwoo	동전 (kriii4_E)	C++14	0 / 100	0 ms	16728 KiB

D

#include<stdio.h>
#include<memory.h>
#define mod 1000000007
#define inv(a) exp(a,mod-2)

typedef long long lld;

lld exp(lld a, lld b){
	if(b<=0)return 1;
	lld k=exp(a, b/2);
	k=(k*k)%mod;
	if(b%2)k=(k*a)%mod;
	return k;
}

lld fac[1001001], rfac[1001001];

void init(){
	lld i;
	fac[0]=rfac[0]=1;
	for(i=1; i<=1000000; i++){
		fac[i]=(fac[i-1]*i)%mod;
		rfac[i]=inv(fac[i]);
	}
}

lld comb(lld a, lld b){
	return fac[a]*rfac[b]%mod*rfac[a-b]%mod;
}

lld n, grd[251], dy[251];
bool chk[251];

int main(){
	lld i, j, k;
//	init();
	scanf("%d", &n);
	printf("%lld", exp(2,n-2));
	return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 95