What is the problem with my code?

general
1

#include<stdio.h>
int main()
{
int x;
double y;
scanf("%d,%f",&x,&y);
if(x%5==0&&y>x+0.50)
{
double a=y-(x+0.50);
printf("%f",a);
}
else
printf("%f",y);

return 0;
}

2

y equal to x+0.5 should be permitted.