C :

#include<stdio.h>
#include<string.h>
int main(){
char a[100];
char b[100];
char c[100];
char *max;
scanf("%s",a);
scanf("%s",b);
scanf("%s",c);
max=a;
if(strcmp(max,b)<0)
  max=b;
if(strcmp(max,c)<0)
  max=c;
printf("%s\n",max);
return 0;
}

C++ :

#include <stdio.h>
#include <string.h>
int main() {
	char string[101];
	char str[3][101];
	int i;
	for (i = 0;i < 3;i++)
		scanf("%s", str[i]);
	if (strcmp(str[0], str[1]) > 0)
		strcpy(string, str[0]);
	else
		strcpy(string, str[1]);
	if (strcmp(str[2], string) > 0)
		strcpy(string, str[2]);
	printf("%s\n", string);
	return 0;
}

Pascal :

var
  i:longint;
  n,max:string;
begin
  for i:=1 to 3 do
  begin
    readln(n);
    if n>max then max:=n;
  end;
  writeln(max);
end.

Java :

import java.util.Arrays;
import java.util.Scanner;

public class Main{
   private static Scanner s = new Scanner(System.in) ;
   
   public static void main(String[] args) {
	  String strs[] = new String[3] ;
	  for (int i = 0; i < strs.length; i++) {
		strs[i] = s.next() ;
	  } 
	  
	  Arrays.sort(strs);
	  
	  System.out.println(strs[strs.length-1]) ;
   }
}