Program to find the difference between given two numbers

#include
float ratio(int x, int y, int z);
int difference(int x, int y);
main()
{
 int a, b, c;
scanf("%d %d %d", &a, &b, &c);
printf("%f \n", ratio(a,b,c));
getch();
}

float ratio(int x, int y, int z)
{
 if(difference(y,z))
  return(x/(y-z));
 else
  return(0.0);
}

int difference(int p, int q)
{
 if(p!=q)
  return(1);
 else
  return(0);
}