ACM——Tutor（水题一枚）

题目传送门：http://acm.hdu.edu.cn/showproblem.php?pid=4493

题目如下：

Problem Description

Lilin was a student of Tonghua Normal University. She is studying at University of Chicago now. Besides studying, she worked as a tutor teaching Chinese to Americans. So, she can earn some money per month. At the end of the year, Lilin wants to know his average monthly money to decide whether continue or not. But she is not good at calculation, so she ask for your help. Please write a program to help Lilin to calculate the average money her earned per month.

 

Input

The first line contain one integer T, means the total number of cases. 
Every case will be twelve lines. Each line will contain the money she earned per month. Each number will be positive and displayed to the penny. No dollar sign will be included.

 

Output

The output will be a single number, the average of money she earned for the twelve months. It will be rounded to the nearest penny, preceded immediately by a dollar sign without tail zero. There will be no other spaces or characters in the output.

Sample Input

2 

100.00 489.12 12454.12 1234.10 823.05 109.20 5.27 1542.25 839.18 83.99 1295.01 1.75 

100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00

 

 

Sample Output

$1581.42 

$100

代码如下：

/*****  简单ACM水题 ********//******** written by C_Shit_Hu ************/////////////////2013通化邀请赛////////////////****************************************************************************//* 求平均数，然后按照规定格式输出即可。注意末尾的0，不用输出。*//****************************************************************************/#include <stdio.h>#include <string.h>int main(){// freopen("in.txt","r",stdin);// freopen("out.txt","w",stdout);    int T, len, i;char str[1000];    scanf("%d",&T);    while(T--)    {        double sum = 0;        double a;        for(i = 0;i < 12;i++)        {            scanf("%lf",&a);            sum += a;        }        sum /= 12;        sprintf(str,"%.2f",sum);        len = strlen(str);        if(str[len-2] == '0' && str[len-1] == '0')            str[len-3] = '\0';    // 或者直接赋值为0， 即是str[len-2] = 0;(即是赋值为空)        else if(str[len-1] == '0')            str[len-1] = '\0';        printf("$%s\n",str);    }    return 0;}/******************************************************//********************  心得体会  **********************//**//******************************************************/

运行结果：