C++ :

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
void swap(char *p,char *q)
{
	char str[50];
	strcpy(str,p);
	strcpy(p,q);
	strcpy(q,str);
}
int main()
{
	char s1[50],s2[50],s3[50];
	char *p1=s1,*p2=s2,*p3=s3;
	gets(p1); gets(p2); gets(p3);
	if (strcmp(p1,p2)>0) swap(p1,p2);
	if (strcmp(p1,p3)>0) swap(p1,p3);
	if (strcmp(p2,p3)>0) swap(p2,p3);
	printf("%s\n%s\n%s\n",p1,p2,p3);
	return 0;
}

Pascal :

var x:string;
    y,z,i,j:integer;
    a:array [1..3] of string;
begin
  for i:=1 to 3 do readln(a[i]);
  for i:=1 to 3 do
   for j:=1 to 3 do
   if a[i]>a[j] then begin x:=a[i]; a[i]:=a[j]; a[j]:=x; end;
   for i:=3 downto 1 do writeln(a[i]);
    
end.