Submission #15186

#	Time	Username	Problem	Language	Result	Execution time	Memory
15186		gs13068	맛있는 과자 (kriii3_A)	C++98	33 / 33	0 ms	1204 KiB

A

#include<cstdio>
#include<cmath>

long long d[44][44];

int main()
{
    double res;
    int i,j,a,b,n;
    long long k;
    scanf("%d%d%d%lld",&a,&b,&n,&k);
    if(a<b)a^=b^=a^=b;
    for(i=0;i<=n;i++)
    {
        d[i][0]=d[i][i]=1;
        for(j=1;j<i;j++)d[i][j]=d[i-1][j]+d[i-1][j-1];
    }
    for(j=0;j<=n;j++)
    {
        if(k>d[n][j])k-=d[n][j];
        else break;
    }
    res=log(a*b/2.);
    for(i=0;i<j;i++)res+=log(1.*b*b/(a*a+b*b));
    for(i=j;i<n;i++)res+=log(1.*a*a/(a*a+b*b));
    printf("%.12lf\n",res);
}

• Subtask 1: 10 / 10
• Subtask 2: 23 / 23