Probability

Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 2313    Accepted Submission(s): 1146


Problem Description
Mickey is interested in probability recently. One day , he played a game which is about probability with mini.First mickey gives a letter and a word to mini.Then mini calculate the probability that the letter appears in the word.For example,give you the letter "a" and the word "apple". the probability of this case is 0.20000.
 

 

Input
The input contains several test cases. Each test case consists of a letter and a word.The length of the word is no longer than 200.
 

 

Output
For each test case, print the probability rounded to five digits after the decimal point.
 

 

Sample Input
a apple c Candy a banana
 

 

Sample Output
0.20000 0.20000 0.50000
 

 

Author
KiKi
 

 

Source
HDU 2007-11 Programming Contest_WarmUp
 

 

Recommend
威士忌
 
 
#include<stdio.h>
#include<string.h>
char str[210];
int main()
{
    char ch1,ch2;
    while(scanf("%c %s",&ch1,&str)!=EOF)
    {
        if(ch1>='a'&&ch1<='z')ch2=ch1-'a'+'A';
        else ch2=ch1-'A'+'a';
        int len=strlen(str);
        int tt=0;
        for(int i=0;i<len;i++)
        {
            if(str[i]==ch1||str[i]==ch2)tt++;
        }    
        printf("%.5lf\n",(double)tt/len);
        getchar();
    }    
    return 0;
}

文章来源:http://www.cnblogs.com/kuangbin/archive/2011/11/15/2249142.html