- Write a C program to sort to an array in decreasing order using bubble sort.

#### Required Knowledge

Given an unsorted integer array, we have to **sort the elements of the array in decreasing order**. As the index of the array increases, the values of the elements should decrease.

For Example:

Input Array : 2 8 4 9 1 0

Output Array : 9 8 4 2 1 0

**Algorithm to sort an array in decreasing order using bubble sort**

*Let inputArray is an integer array having N elements.*

**Bubble sort**compares two adjacent element of an array and will swap them if they are out of order. If inputArray [i] < inputArray[i+1] then we will swap elements at position i and i+1 as they are not in decreasing order. As we are sorting in decreasing order, element at index i must be greater than element in i+1 in sorted array.- If inputArray [i] >= inputArray[i+1] then we should not swap elements at position i and i+1 as they are already in decreasing order.
- Next, we will compare i+1 and i+2, then i+2 amd i+3 and so on... till end of the array.
- If there are N element then we have to repeat above process N-1 times because in every traversal we will put largest element of unsorted sub-array in its sorted position.

## C program to sort an array in decreasing order using bubble sort

#include <stdio.h> #include <conio.h> int main() { int inputArray[100], elementCount, index, i, j, temp; printf("Enter Number of Elements in Array\n"); scanf("%d", &elementCount); printf("Enter %d numbers \n", elementCount); /* Read array elements */ for(index = 0; index < elementCount; index++){ scanf("%d", &inputArray[index]); } /* Sort Array in decreasing order using Bubble Sort */ for(i = 0; i < elementCount; i++) { for(j = 0; j < elementCount-i-1; j++) { if(inputArray[j] < inputArray[j+1]) { /* Swap inputArray[j] and inputArray[j+1] */ temp = inputArray[j]; inputArray[j] = inputArray[j+1]; inputArray[j+1] = temp; } } } printf ("Sorted Array in Decreasing Order\n") ; /* Print Sorted Array */ for(index = 0; index < elementCount; index++){ printf("%d ", inputArray[index]); } getch(); }Output

Enter Number of Elements in Array 7 Enter 7 numbers 1 6 3 0 7 2 9 Sorted Array in Decreasing Order 9 7 6 3 2 1 0

Enter Number of Elements in Array 8 Enter 8 numbers 1 2 1 2 1 2 1 2 Sorted Array in Decreasing Order 2 2 2 2 1 1 1 1

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