C++ sort() Sorts array of strings with user-written comparison function

#include <iostream>
#include <string>                       // for strcmp()
#include <algorithm>
using namespace std;
// array of strings
char* names[] = { "G", "P", "E","D", "M", "B", "P", "E","D", "M", "B" };
bool alpha_comp(char*, char*);          // declaration
int main()/*from  w  w  w . j a v  a 2  s .  co  m*/
{
   sort(names, names+6, alpha_comp);    // sort the strings
   for(int j=0; j<6; j++)               // display sorted strings
      cout << names[j] << endl;
   return 0;
}
bool alpha_comp(char* s1, char* s2)     // returns true if s1<s2
{
   return ( strcmp(s1, s2)<0 ) ? true : false;
}