C :

# include <stdio.h>
int main ()
{
  int max ( int x, int y);
  int a, b, c;
  scanf("%d %d",&a,&b);
  c = max( a, b);
  printf("max=%d\n",c);
  return 0;
}
int max(int x, int y)
{
  int z;
  if (x>y)
    z=x;
  else
    z=y;
  return(z);
}

C++ :

#include<stdio.h>
int main()
{
	int a,b,max;
	scanf("%d %d",&a,&b);
	if(a<=b)
	{
		max=b;
		printf("max=%d\n",max);
	}
	else
	{
	    max=a;
		printf("max=%d\n",max);
	}
		return 0;
}

Pascal :

var
  a,b:longint;
begin
  read(a,b);
  if a>b then writeln('max=',a)
else writeln('max=',b);
end.