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I don't know why I get WA though I have check many inputs and outputs.Please help me,thanks in advance!
#include<stdio.h>
#include<math.h>
int main(void)
{
int h,m;
double a;
while(scanf("%i:%i",&h,&m)!=EOF && (h||m))
{
a=fabs(5.5*m-30*h);
if(a-180>1e-9)
a=360-a;
printf("%.3f\n",a ...