Selection Sort is one of the most beginner-friendly sorting algorithms in C programming. It works by repeatedly selecting the smallest element from an unsorted part of an array and placing it in the correct position.<\/p>\n\n\n\n
Although it is not the fastest sorting algorithm for large datasets, Selection Sort helps beginners understand sorting logic, array traversal, swapping, and nested loops in C.<\/p>\n\n\n\n
In this article, you will learn what is Selection Sort in C, how the algorithm works, its syntax, time complexity, advantages, disadvantages, and how to implement it with a complete C program and examples.<\/p>\n\n\n\n
Selection Sort is a sorting algorithm that repeatedly selects the smallest element from the unsorted part of an array and places it at the beginning.<\/p>\n\n\n\n
The process continues until all elements are in sorted order.<\/p>\n\n\n\n
The algorithm divides the array into two parts:<\/p>\n\n\n\n
In every iteration, the smallest element from the unsorted section is selected and swapped with the first unsorted element.<\/p>\n\n\n\n
Selection Sort is one of the first sorting algorithms<\/a> taught in programming because it helps beginners understand how comparison-based sorting works.<\/p>\n\n\n\n Before learning more complex algorithms like Merge Sort <\/a>or Quick Sort<\/a>, students often start with Selection Sort to build confidence in:<\/p>\n\n\n\n Even though modern applications rarely use Selection Sort for large datasets, understanding its logic creates a strong foundation for learning data structures and algorithms.<\/p>\n\n\n\n Another reason beginners learn Selection Sort is that the algorithm is predictable and easy to dry-run manually.<\/p>\n\n\n\n Unlike some advanced sorting techniques that involve recursion or partitioning logic, Selection Sort follows a direct step-by-step process.<\/p>\n\n\n\n Selection Sort works through repeated comparisons.<\/p>\n\n\n\n The algorithm scans the array to find the smallest element and swaps it into the correct position.<\/p>\n\n\n\n The steps are:<\/p>\n\n\n\n Suppose the array is:<\/p>\n\n\n\n 64, 25, 12, 22, 11<\/p>\n\n\n\n 11, 25, 12, 22, 64<\/p>\n\n\n\n 11, 12, 25, 22, 64<\/p>\n\n\n\n 11, 12, 22, 25, 64<\/p>\n\n\n\n The array is now sorted.<\/p>\n\n\n\n The basic Selection Sort algorithm is:<\/p>\n\n\n\n Below is the complete C program<\/a> for Selection Sort.<\/p>\n\n\n\n include <stdio.h><\/p>\n\n\n\n int main() {<\/p>\n\n\n\n int arr[] = {64, 25, 12, 22, 11};<\/p>\n\n\n\n int n = 5;<\/p>\n\n\n\n int i, j, minIndex, temp;<\/p>\n\n\n\n for(i = 0; i < n – 1; i++) {<\/p>\n\n\n\n minIndex = i;<\/p>\n\n\n\n for(j = i + 1; j < n; j++) {<\/p>\n\n\n\n if(arr[j] < arr[minIndex]) {<\/p>\n\n\n\n minIndex = j;<\/p>\n\n\n\n }<\/p>\n\n\n\n }<\/p>\n\n\n\n temp = arr[minIndex];<\/p>\n\n\n\n arr[minIndex] = arr[i];<\/p>\n\n\n\n arr[i] = temp;<\/p>\n\n\n\n }<\/p>\n\n\n\n printf(“Sorted array:\\n”);<\/p>\n\n\n\n for(i = 0; i < n; i++) {<\/p>\n\n\n\n printf(“%d “, arr[i]);<\/p>\n\n\n\n }<\/p>\n\n\n\n return 0;<\/p>\n\n\n\n }<\/p>\n\n\n\n The outer loop controls the number of passes needed for sorting.<\/p>\n\n\n\n The inner loop searches for the smallest element in the unsorted part of the array.<\/p>\n\n\n\n Once the minimum element is found, swapping is done using a temporary variable.<\/p>\n\n\n\n Finally, the sorted array is displayed using a loop.<\/p>\n\n\n\n Sorted array:<\/p>\n\n\n\n 11, 12, 22, 25, 64<\/p>\n\n\n\n You can also explore HCL GUVI\u2019s <\/strong>DSA ebook<\/strong><\/a> to understand sorting algorithms, arrays, searching techniques, and core programming concepts used in data structures and algorithms.<\/p>\n\n\n\n Understanding the dry run helps beginners visualize how the algorithm works internally.<\/p>\n\n\n\n Consider the array:<\/p>\n\n\n\n 29, 10, 14, 37, 13<\/p>\n\n\n\n 29, 10, 14, 37, 13<\/p>\n\n\n\n Updated array:<\/p>\n\n\n\n 10, 29, 14, 37, 13<\/p>\n\n\n\n Updated array:<\/p>\n\n\n\n 10, 13, 14, 37, 29<\/p>\n\n\n\n Updated array:<\/p>\n\n\n\n 10, 13, 14, 37, 29<\/p>\n\n\n\n Final sorted array:<\/p>\n\n\n\n 10, 13, 14, 29, 37<\/p>\n\n\n\n This repeated process of selecting the minimum value gives Selection Sort its name.<\/p>\n\n\n\n Selection Sort performs comparisons repeatedly regardless of the input arrangement.<\/p>\n\n\n\n\n
How Does Selection Sort Work?<\/strong><\/h2>\n\n\n\n
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Pass 1<\/strong><\/h3>\n\n\n\n
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Pass 2<\/strong><\/h3>\n\n\n\n
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Pass 3<\/strong><\/h3>\n\n\n\n
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Selection Sort Algorithm<\/strong><\/h2>\n\n\n\n
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C Program for Selection Sort<\/strong><\/h2>\n\n\n\n
Explanation<\/strong><\/h3>\n\n\n\n
Output Example<\/strong><\/h2>\n\n\n\n
Dry Run of Selection Sort<\/strong><\/h2>\n\n\n\n
Initial Array<\/strong><\/h3>\n\n\n\n
First Iteration<\/strong><\/h3>\n\n\n\n
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Second Iteration<\/strong><\/h3>\n\n\n\n
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Third Iteration<\/strong><\/h3>\n\n\n\n
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Fourth Iteration<\/strong><\/h3>\n\n\n\n
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Time Complexity of Selection Sort<\/strong><\/h2>\n\n\n\n