Selection Sort

C Implementation of Selection Sort Technique

Selection Sort:

1. Has the time complexity of O(n^2)
2. Logic:
• Find the index of the minimum element from the array from 0 to n-1
• Swap the minimum value with the value in the 0th index
• Again, Find the index of the minimum element from the array from 1 to n-1
• Swap the minimum value with the value in the 1st index
• Repeat the process till you reach the (n-1)th index of the array

#include <stdio.h> #include <stdlib.h> /* function selection sort to sort the elements in non-decreasing order */ void selectionsort(int *A,int n) { int temp,i,j,imin; /* from 0th index of the array till n-1 th index of the array */ for(i=0;i<n-1;i++) { /* assume ith index to be index of the minimum value of the array */ imin=i; /* find the index of the minimum value in the whole array by comparisons */ for(j=i+1;j<n;j++) { if(*(A+j)<*(A+imin)) imin=j; } /* swap the ith index with the index of the minimum value in the array */ temp=*(A+i); *(A+i)=*(A+imin); *(A+imin)=temp; } } int main(void) { /* Input unsorted array */ int A[]={5,2,4,8,6,8,7,3,1}; /* calculate the size of the array or number of elements in the array */ int size=sizeof(A)/sizeof(*A); int i; /* function call to perform selection sort */ selectionsort(A,size); /* printing the values in the sorted array */ for(i=0;i<size;i++) printf("%d ",*(A+i)); return 0; }