C :

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

C++ :

#include<iostream>
using namespace std;
int main()
{
int a,b,c;
cin>>a>>b>>c;
if(a>b&&a>c)
cout<<a;
if(b>a&&b>c)
cout<<b;
if(c>b&&c>a)
cout<<c;
}

Pascal :

var s,i,t,j:integer;
    a:array [1..3] of integer;
begin
  for i:=1 to 3 do read(a[i]);

  for i:=1 to 3-1 do
   for j:=i+1 to 3 do
   if a[i]<a[j] then begin t:=a[i]; a[i]:=a[j]; a[j]:=t; end;
   write(a[1]);
end.