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

Chapter 10 ■ Structures
Given the previous data, the call
search("Singh, Sandy", pupil, 4)
will return 2, and the following call will return -1:
search("Layne, Sandy", pupil, 4)
10.5 Sort an Array of Structure
Suppose we want the list of students in alphabetical order by name. It will be required to sort the
array pupil. The following function uses an insertion sort to do the job. The process is identical to
sorting an int array, say, except that the name field is used to govern the sorting.
void sort(Student list[], int n) {
//sort list[0] to list[n-1] by name using an insertion sort
Student temp;
int k;
for (int h = 1; h < n; h++) {
Student temp = list[h];
k = h - 1;
while (k >= 0 && strcmp(temp.name, list[k].name) < 0) {
list[k + 1] = list[k];
k = k - 1;
}
}
list[k + 1] = temp;
} //end sort
Observe this statement:
list[k + 1] = list[k];
This assigns all the fields of list[k] to list[k+1].
If we want to sort the students in order by age, all we need to change is the while condition.
To sort in ascending order, we write this:
while (k >= 0 && temp.age < list[k].age)
//move smaller numbers to the left
To sort in descending order, we write this:
while (k >= 0 && temp.age > list[k].age)
//move bigger numbers to the left
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