답안 #20045

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
20045 2016-02-25T08:51:35 Z suzy 괄호 (kriii4_R) C++
8 / 100
405 ms 16708 KB
#include <stdio.h>
 
#define MOD 1000000007
 
typedef long long lli;
 
lli f[1000001];
lli inv[1000001];
 
lli p(lli a, lli x) {
    if(x==0) return 1;
    if(x%2) return a*p(a,x-1)%MOD;
    else { lli m=p(a,x/2); return m*m%MOD; }
}
 
lli C(lli k) {
    lli ret=f[2*k]*inv[k]%MOD;
    return ret*inv[k+1]%MOD;
}
 
int main() {
    int n, k;
    f[0]=f[1]=1;
    for(lli i=2;i<=1000000;i++)
        f[i]=f[i-1]*i%MOD;
    for(lli i=0;i<=1000000;i++)
        inv[i]=p(f[i],MOD-2);
    scanf("%d %d",&n,&k);
    lli res=0, t=1;
    for(lli l=1;l<=n;l++) {
        if(l%2) t=(t*2-C((l-1)/2)+MOD)%MOD;
        else t=t*2%MOD;
    }
    printf("%lld",t);
}
# 결과 실행 시간 메모리 Grader output
1 Correct 399 ms 16708 KB Output is correct
2 Correct 394 ms 16708 KB Output is correct
3 Correct 404 ms 16708 KB Output is correct
4 Correct 402 ms 16708 KB Output is correct
5 Correct 405 ms 16708 KB Output is correct
6 Correct 402 ms 16708 KB Output is correct
7 Correct 394 ms 16708 KB Output is correct
8 Correct 400 ms 16708 KB Output is correct
9 Correct 395 ms 16708 KB Output is correct
10 Correct 398 ms 16708 KB Output is correct
11 Correct 394 ms 16708 KB Output is correct
12 Correct 402 ms 16708 KB Output is correct
13 Correct 396 ms 16708 KB Output is correct
14 Correct 396 ms 16708 KB Output is correct
15 Correct 396 ms 16708 KB Output is correct
16 Correct 396 ms 16708 KB Output is correct
17 Correct 404 ms 16708 KB Output is correct
18 Correct 403 ms 16708 KB Output is correct
19 Correct 398 ms 16708 KB Output is correct
20 Correct 403 ms 16708 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Incorrect 399 ms 16708 KB Output isn't correct
2 Halted 0 ms 0 KB -