HDU 2003 - 求绝对值

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=2003

#include <math.h>#include <stdio.h>int main(void){    double r;    while (scanf("%lf", &r) != EOF)        printf("%.2lf\n", fabs(r));    return 0;}