답안 #20058

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
20058	2016-02-25T08:57:41 Z	Namnamseo	카드 (kriii4_Z)	C++14	13 / 100	137 ms	87912 KB

Z

#include<cstdio>
#include<cstring>
long long po[3333],a,b,i,c,aa,bb=1,x,X=1e9+7,D[3333][3333];
long long pow(long long aa,long long bb){
    if(bb==0) return 1;
    long long ret=pow(aa,bb/2);
    ret=(ret*ret)%X;
    if(bb&1) ret=(ret*aa)%X;
    return ret;
}
long long f(long long C,long long L)
{
    if(D[C][L]>=0)return D[C][L];
    if(C==0&&L>=0)return D[C][L]=po[L];
    if(L==0)return D[C][L]=0;
    if(C>L)return D[C][L]=0;
    return D[C][L]=(C*f(C-1,L-1)%X+(a-C)*f(C,L-1)%X)%X;
}
main()
{
    memset(D,-1,sizeof(D));
    scanf("%lld%lld",&a,&b);
    for(i=1;i<=a;i++){scanf("%lld",&x);if(x==1)c++;};
    if(c==0)
    {
        printf("1");
        return 0;
    }
    po[0]=1;
    for(i=1;i<=b;i++)po[i]=po[i-1]*a%X;
    aa=f(c,b);
    printf("%lld",aa*pow(po[b],X-2)%X);
}

Subtask #1

13.0 / 13.0

#	결과	실행 시간	메모리	Grader output
1	Correct	81 ms	87908 KB	Output is correct
2	Correct	106 ms	87908 KB	Output is correct
3	Correct	0 ms	87896 KB	Output is correct
4	Correct	103 ms	87904 KB	Output is correct
5	Correct	117 ms	87900 KB	Output is correct
6	Correct	51 ms	87896 KB	Output is correct
7	Correct	127 ms	87896 KB	Output is correct
8	Correct	105 ms	87896 KB	Output is correct
9	Correct	71 ms	87904 KB	Output is correct
10	Correct	80 ms	87896 KB	Output is correct
11	Correct	120 ms	87904 KB	Output is correct
12	Correct	64 ms	87900 KB	Output is correct
13	Correct	106 ms	87896 KB	Output is correct
14	Correct	137 ms	87904 KB	Output is correct
15	Correct	11 ms	87896 KB	Output is correct
16	Correct	85 ms	87896 KB	Output is correct
17	Correct	127 ms	87904 KB	Output is correct
18	Correct	103 ms	87896 KB	Output is correct
19	Correct	17 ms	87912 KB	Output is correct
20	Correct	102 ms	87896 KB	Output is correct
21	Correct	8 ms	87912 KB	Output is correct
22	Correct	12 ms	87912 KB	Output is correct
23	Correct	4 ms	87912 KB	Output is correct
24	Correct	7 ms	87908 KB	Output is correct
25	Correct	4 ms	87908 KB	Output is correct

Subtask #2

0.0 / 87.0

#	결과	실행 시간	메모리	Grader output
1	Incorrect	118 ms	87900 KB	Output isn't correct
2	Halted	0 ms	0 KB	-