(Alphabetizing Animal Names) Write a program that uses the comparison capabilities in- troduced in this chapter to alphabetize a series of animal names. Only uppercase letters should be used for the comparisons.

Question

What will be an ideal response?

Answer 1

```
// NOTE: The problem description should have asked
// the programmer to use a quicksort.
#include
#include
using namespace std;

// prototypes
void output( const string *, const int );
void quickSort( string [], int, int );
int partition( string [], int, int );

int main()
{
const int SIZE = 19;

// an array of strings containing animal names
string animals[] = { "Macaw", "Lion", "Tiger", "Bear", "Toucan",
"Zebra", "Puma", "Cat", "Yak", "Boar", "Fox", "Ferret",
"Crocodile", "Alligator", "Elk", "Ox", "Horse", "Eagle", "Hawk" };

cout << "before:";
output( animals, SIZE ); // call output to display string array
quickSort( animals, 0, SIZE ); // sort them in order

cout << "\nafter:";
output( animals, SIZE ); // call output to display array of animal
} // end main

// function to print out each string in the array
void output( const string * const ani, const int length )
{
// loop through the array with the given length
for ( int j = 0; j < length; ++j )
cout << ( j % 10 ? ' ': '\n' ) << ani[ j ];

cout << endl;
} // end function output

// function to sort the array
void quickSort( string a[], int first, int last )
{
// call function partition
int currentLocation;

if ( first >= last )
return;

currentLocation = partition( a, first, last );

// recursive calls to quickSort to continue the search
quickSort( a, first, currentLocation - 1 );
quickSort( a, currentLocation + 1, last );
} // end function quickSort

int partition( string b[], int left, int right )
{
int pos = left;

// while loop
while ( true )
{
// move through the array from left to right
while ( b[ pos ] <= b[ right ] && pos != right )
right--;

// if the right is reached, return that position
if ( pos == right )
return pos;

// if the element from the left is greater, swap the positions
if ( b[ pos ] > b[ right ] )
{
b[ pos ].swap( b[ right ] );
pos = right;
} // end if

// compare from the beginning to the pos index
while ( b[ left ] <= b[ pos ] && pos != left )
left++;

if ( pos == left )
return pos;

if ( b[ left ] > b[ pos ] )
{
b[ pos ].swap( b[ left ] );
pos = left;
} // end if
} // end while
} // end function partition
```
before:
Macaw Lion Tiger Bear Toucan Zebra Puma Cat Yak Boar
Fox Ferret Crocodile Alligator Elk Ox Horse Eagle Hawk
after:
Alligator Bear Boar Cat Crocodile Eagle Elk Ferret Fox Hawk
Horse Lion Macaw Ox Puma Tiger Toucan Yak Zebra