poj 1004

Financial Management

Time Limit: 1000MS		Memory Limit: 10000K
Total Submissions: 104137		Accepted: 49985

Description

Larry graduated this year and finally has a job. He's making a lot of money, but somehow never seems to have enough. Larry has decided that he needs to grab hold of his financial portfolio and solve his financing problems. The first step is to figure out what's been going on with his money. Larry has his bank account statements and wants to see how much money he has. Help Larry by writing a program to take his closing balance from each of the past twelve months and calculate his average account balance.

Input

The input will be twelve lines. Each line will contain the closing balance of his bank account for a particular 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 (mean) of the closing balances for the twelve months. It will be rounded to the nearest penny, preceded immediately by a dollar sign, and followed by the end-of-line. There will be no other spaces or characters in the output.

Sample Input

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

Sample Output

$1581.42

解:该题的阶梯思路很简单,把输入的十二个数求平均,该题的关键是结果取两位小数,并且要按照四舍五入规则取整,c语言的printf自带结果近似,如printf("%.2f", a)表示结果取两位有效数字.总的代码如下:

#include <stdio.h>

int main(int argc, char const *argv[])
{
    float total = 0.0, a;
    for(int i = 0; i < 12; ++i){
        scanf("%f", &a);
        total += a;
    }
    printf("$%.2f\n", total/12.0);
    return 0;
}