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SelectionSort.c
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SelectionSort.c
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// Pseudocode
// bucket numbers : 0, 1, 2, 3 ...98, 99
#include <stdio.h>
#include <stdlib.h>
int *generateArray(int n) {
int *array = malloc( n * sizeof(int) );
if(array) {
for(int i=0; i<n; i++)
{
array[i] = rand()%1000; // Randomly allocate and take the mod of thoes each values( coz num generated are big) and saves in an array
}
}
return array; //Doubtful if this return the starting address of array t or not.
}
void printArray(int *a, int n) { // better version of printing the elements of array than PrintArray1() function.
for(int i=0; i<n; i++) {
printf( i?", %d":"%d", a[i]); //Ternery operator to check where to put commas.
}
printf(".\n");
}
int IndexOfMaxElement(int *a, int n)
{
int maxI;
if(n<1) return 0; //error case if there are no elements in the list return 0 and move out of function.
maxI = 0; // I am assuming a[0] is the max element.
for (int i=1; i<n; i++){
if(a[i] > a[maxI]){
maxI = i;
}
}
return maxI; //Returns the maximum Index
}
void swap(int *x, int *y) // Call by reference changes the address location of the element directly in the array without creating the copy of that array.
{
int t;
t = *x; // t = value at address x
*x = *y; // At address x, the value of y is stored.
*y = t;
}
void selectionSort(int *a, int n)
{
// here n = 100
int i;
int imax; // this will contain index of the maximum element in an array
for (i = n; i > 1; i = i - 1) // i!>0 coz we are assuming that the
{
imax = IndexOfMaxElement(a, i);
swap(&a[imax], &a[i-1]); // OR swap(a+imax, a+i-1)
}
}
void swap2(int x, int y) // This function is just for my understanding of Call by Value concept.
{
int t = x;
x = y;
y = t;
}
// Here if we call swap2 functions from the main(), then print the value of x there, value of x wont be swapped. This is because of Call by Value as the copies of x and y are sent
int main(int argc, char **argv){
int n;
int *array;
printf("Enter the size of array:");
scanf("%d", &n);
array = generateArray(n);
printf("Original Array = ");
printArray(array, n);
selectionSort(array, n);
printf("Sorted Array = ");
printArray(array, n);
return 0;
}