//ex2: sort by index : odd index & even index
#include<stdio.h>
#include<stdlib.h>

int inputArray(int arr[], int size);
void sortArraybyIndex(int arr[], int size);

int main(){
	int arr[50], size;
	size = inputArray(arr, size);
	sortArraybyIndex(arr, size);
	return 0;
}

int inputArray(int arr[], int size){
	printf("Enter size of Array: ");
	scanf("%d", &size);
	for(int i = 0; i < size; i++){
		printf("arr[%d] = ", i);
		scanf("%d", &arr[i]);
	}
	return size;
}

void sortArraybyIndex(int arr[], int size){
	int temp;
	//sort Ascending if index is odd
	for(int i = 0; i < size; i+=2){
		for(int j = i + 2; j < size; j+=2){
			if(arr[i] > arr[j]){
				temp = arr[i];
				arr[i] = arr[j];
				arr[j] = temp;
			}
		}
	}
	
	//sort Descending if index is Even
	for(int i = 1; i < size; i+=2){
		for(int j = i + 2; j < size; j+=2){
			if(arr[i] < arr[j]){
				temp = arr[i];
				arr[i] = arr[j];
				arr[j] = temp;
			}
		}
	}	
	
	//Display the array
	printf("The Array after sort:\n");
	for(int i = 0; i < size; i++){
		printf("arr[%d] = %d\n", i, arr[i]);
	}
}