Revise the method selectionSort that appears in Listing 7.10 so that it calls the method described in
Question:
Revise the method selectionSort that appears in Listing 7.10 so that it calls the method described in the previous exercise.
Listing 7.10
/**
Class for sorting an array of base type int from smallest to largest.
*/
public class ArraySorter
{
/**
Precondition: Every element in anArray has a value.
Action: Sorts the array into ascending order.
*/
public static void selectionSort(int[] anArray)
{
for (int index = 0; index < anArray.length − 1; index++)
{ // Place the correct value in anArray[index]
int indexOfNextSmallest = getIndexOfSmallest(index,
anArray);
interchange(index, indexOfNextSmallest, anArray);
//Assertion:anArray[0] <= anArray[1] <=…<= anArray[index]
//and these are the smallest of the original array elements.
//The remaining positions contain the rest of the original
//array elements.
}
}
/**
Returns the index of the smallest value in the portion of the
array that begins at the element whose index is startIndex and
ends at the last element.
*/
private static int getIndexOfSmallest(int startIndex, int[] a)
{
int min = a[startIndex];
int indexOfMin = startIndex;
for (int index = startIndex + 1; index < a.length; index++)
{
if (a[index] < min)
{
min = a[index];
indexOfMin = index;
//min is smallest of a[startIndex] through a[index]
}
}
return indexOfMin;
}
/**
Precondition: i and j are valid indices for the array a.
Postcondition: Values of a[i] and a[j] have been interchanged.
*/
private static void interchange(int i, int j, int[] a)
{
int temp = a[i];
a[i] = a[j];
a[j] = temp; //original value of a[i]
}
}
Step by Step Answer:
Java An Introduction To Problem Solving And Programming
ISBN: 9780134462035
8th Edition
Authors: Walter Savitch