zoj 3827 Information Entropy

#include <stdio.h>#include <string.h>#include <math.h>const double e=exp(1.0);double find(char op[]){    if(op[0]=='b')        return 2.0;    else if(op[0]=='n')        return e;    else if(op[0]=='d')        return 10.0;}int main(){    int t,i,n;    double p[210],b;    char op[20];    scanf("%d",&t);    while(t--)    {        scanf("%d %s",&n,op);        b=find(op);        double ans=0.0;        for(i=0;i<n;i++)        { scanf("%lf",&p[i]); p[i]/=100.0;if(p[i]!=0.0)ans+=p[i]*log(p[i])/log(b);        }        printf("%.12lfn",-ans);    }return 0;}