Bubble Sort
Bubble Sort is an elementary sorting algorithm. It works by repeatedly exchanging adjacent elements, if necessary. When no exchanges are required, the file is sorted.
SEQUENTIAL BUBBLESORT (A)
for i ← 1 to length [A] do
for j ← length [A] downto i +1 do
If A[A] < A[j-1] then
Exchange A[j] ↔ A[j-1]
Here the number of comparison made
1 + 2 + 3 + . . . + (n - 1) = n(n - 1)/2 = O(n2)
Clearly, the graph shows the n2 nature of the bubble sort.
In this algorithm the number of comparison is irrespective of data set i.e., input whether best or worst.
Memory Requirement
Clearly, bubble sort does not require extra memory.Implementation
void bubbleSort(int numbers[], int array_size) { int i, j, temp; for (i = (array_size - 1); i >= 0; i--) { for (j = 1; j <= i; j++) { if (numbers[j-1] > numbers[j]) { temp = numbers[j-1]; numbers[j-1] = numbers[j]; numbers[j] = temp; } } } }
Algorithm for Parallel Bubble Sort
PARALLEL BUBBLE SORT (A)
- For k = 0 to n-2
- If k is even then
- for i = 0 to (n/2)-1 do in parallel
- If A[2i] > A[2i+1] then
- Exchange A[2i] ↔ A[2i+1]
- Else
- for i = 0 to (n/2)-2 do in parallel
- If A[2i+1] > A[2i+2] then
- Exchange A[2i+1] ↔ A[2i+2]
- Next k
Parallel Analysis
Steps 1-10 is a one big loop that is represented n -1 times. Therefore, the parallel time complexity is O(n). If the algorithm, odd-numbered steps need (n/2) - 2 processors and even-numbered steps require (n/2) - 1 processors. Therefore, this needs O(n) processors.Links
- Bubble Sort
- Bubble Sort (Ordinary)
- Bubble Sort (Ordinary, with User Input)
- Bubble Sort (More Efficient)
- Bubble Sort (More Efficient, with User Input)
- Simple Sort
- Simple Sort (with User Input)
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