Learn to Program with C_ Learn to Program using the Popular C Programming Language ( PDFDrive )

Chapter 9 ■ Searching, Sorting, and Merging
With getSmallest and swap, we can code the algorithm, above, as a function selectionSort. To
emphasize that we can use any names for our parameters, we write the function to sort an integer
array called list. To make it general, we also tell the function which portion of the array to sort by
specifying subscripts lo and hi. Instead of the loop going from 0 to n-2 as in the algorithm, it now
goes from lo to hi-1 – just a minor change for greater flexibility.
//sort list[lo] to list[hi] in ascending order
void selectionSort(int list[], int lo, int hi) {
int getSmallest(int [], int, int);
void swap(int [], int, int);
for (int h = lo; h < hi; h++) {
int s = getSmallest(list, h, hi);
swap(list, h, s);
}
} //end selectionSort
We now write Program P9.1 to test whether selectionSort works properly. The program
requests up to 10 numbers (since the array is declared to be of size 10), stores them in the array
num, calls selectionSort, then prints the sorted list.
Program P9.1
#include <stdio.h>
int main() {
void selectionSort(int [], int, int);
int v, num[10];
printf("Type up to 10 numbers followed by 0\n");
int n = 0;
scanf("%d", &v);
while (v != 0) {
num[n++] = v;
scanf("%d", &v);
}
//n numbers are stored from num[0] to num[n-1]
selectionSort(num, 0, n-1);
printf("\nThe sorted numbers are\n");
for (int h = 0; h < n; h++) printf("%d ", num[h]);
printf("\n");
} //end main
void selectionSort(int list[], int lo, int hi) {
//sort list[lo] to list[hi] in ascending order
int getSmallest(int [], int, int);
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