C Exercises: Selection sort algorithm

Last update on March 20 2025 12:40:07 (UTC/GMT +8 hours)

1. Selection Sort Variants

Write a C program to sort a list of elements using the selection sort algorithm.

According to Wikipedia "In computer science, selection sort is a sorting algorithm, specifically an in-place comparison sort. It has O(n2) time complexity, making it inefficient on large lists, and generally performs worse than the similar insertion sort".

Note:
a) To find maximum of elements
b) To swap two elements

Pictorial presentation - Selection search algorithm:

C programming Selection sort algorithm

Sample Solution:

Sample C Code:

#include <stdio.h>
  int main()
  {
  int arr[10];
   int i, j, N, temp;
 /* function  declaration */
  int find_max(int  b[10], int k);
  void exchang(int  b[10], int k);
  printf("\nInput no. of values in the array : N");
  scanf("%d",&N);
   printf("\nInput the elements one by one: ");
  for(i=0; i<N ;  i++)
  {
  scanf("%d",&arr[i]);
  }
  /* Selection sorting  begins */
  exchang(arr,N);
  printf("Sorted  array :\n");
  for(i=0; i< N ;  i++)
  {
  printf("%d\n",arr[i]);
  }
}
/* function to find the maximum value */
  int find_max(int b[10], int k)
  {
  int max=0,j;
  for(j = 1; j <=  k; j++)
  {
  if ( b[j] >  b[max])
  {
  max =  j;
  }
  }
  return(max);
  }
  void exchang(int  b[10],int k)
  {
  int  temp, big, j;
  for ( j=k-1;  j>=1; j--)
  {
  big =  find_max(b,j);
  temp = b[big];
  b[big] = b[j];
  b[j] = temp;
  }
  return ;
  }

Sample Input:

Input no. of values in the array : 3
Input  the elements one by one: Sorted  array :15
 56
 12

Sample Output:

Input no. of values in the array : 
Input  the elements one by one: Sorted  array :
12
15
56

Flowchart:

For more Practice: Solve these Related Problems:

Write a C program to sort an array using selection sort recursively and then find the kth smallest element.
Write a C program to modify selection sort to sort in descending order and then print the sorted array.
Write a C program to use selection sort to sort an array of floating-point numbers and display them with fixed decimal precision.
Write a C program to implement selection sort on an array of structures using a specified field as the key.

C Programming Code Editor:

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