C program to store Student records as Structures and Sort them by Name

In this problem, we are given a student’s record which contains student_id, student_name, student_percentage. Our task is to create a C program to store student records as structure and sort them by name.

Let’s take an example to understand the problem,

Input − student record =

{{ student_id = 1, student_name = nupur, student_percentage = 98},
{ student_id = 2, student_name = Akash, student_percentage = 75},
{ student_id = 3, student_name = Yash, student_percentage = 62},
{ student_id = 4, student_name = Jyoti, student_percentage = 87},
{ student_id = 5, student_name = Ramlal, student_percentage = 80}}

Output − student record =

{{ student_id = 2, student_name = Akash, student_percentage = 75},
{ student_id = 4, student_name = Jyoti, student_percentage = 87},
{ student_id = 1, student_name = nupur, student_percentage = 98},
{ student_id = 5, student_name = Ramlal, student_percentage = 80},
{ student_id = 3, student_name = Yash, student_percentage = 62}}

To solve this problem, we will first create a structure that will store the details of the student. Now, we will use qsort() and in that qsort, we will define a comparator function for this qsort that will compare the names of the structure using strcmp() method.

Example

The program to store Student records as Structures and Sort them by Name

//C program to store Student records as Structures and Sort them by Name
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Student {
   int student_id;
   char* student_name;
   int student_percentage;
};
int comparator(const void* s1, const void* s2){
   return strcmp(((struct Student*)s1)->student_name,((struct Student*)s2)->student_name);
}
int main() {
   int n = 5;
   struct Student arr[n];
   //student 1
   arr[0].student_id = 1;
   arr[0].student_name = "Nupur";
   arr[0].student_percentage = 98;
   //student 2
   arr[1].student_id = 2;
   arr[1].student_name = "Akash";
   arr[1].student_percentage = 75;
   //student 3
   arr[2].student_id = 3;
   arr[2].student_name = "Yash";
   arr[2].student_percentage = 62;
   //student 4
   arr[3].student_id = 4;
   arr[3].student_name = "Jyoti";
   arr[3].student_percentage = 87;
   //student 5
   arr[4].student_id = 5;
   arr[4].student_name = "Ramlal";
   arr[4].student_percentage = 80;
   printf("Unsorted Student Record:\n");
   for (int i = 0; i < n; i++) {
      printf("Id = %d, Name = %s, Age = %d \n", arr[i].student_id, arr[i].student_name, arr[i].student_percentage);
   }
   qsort(arr, n, sizeof(struct Student), comparator);
   printf("\n\nStudent Records sorted by Name:\n");
   for (int i = 0; i < n; i++) {
      printf("Id = %d, Name = %s, Age = %d \n", arr[i].student_id, arr[i].student_name, arr[i].student_percentage);
   }
   return 0;
}

Output

Unsorted Student Record:
Id = 1, Name = Nupur, Age = 98
Id = 2, Name = Akash, Age = 75
Id = 3, Name = Yash, Age = 62
Id = 4, Name = Jyoti, Age = 87
Id = 5, Name = Ramlal, Age = 80
Student Records sorted by Name:
Id = 2, Name = Akash, Age = 75
Id = 4, Name = Jyoti, Age = 87
Id = 1, Name = Nupur, Age = 98
Id = 5, Name = Ramlal, Age = 80
Id = 3, Name = Yash, Age = 62