Input Two numbers and output the maximum one

#include "stdio.h"
double max(double x,double y)

{
       if(x>y)
       return (x);
       else
       return (y);
}
int main (void)
{
    double a,b;
    printf("Enter two numbers:\n");
    scanf("%lf %lf", &a,&b);
    printf("The maximum number is %lf\n",max(a,b));
    system("pause");
    return 0;
}