Dr. Sajib Datta Feb 14, 2014

 Ordering elements in some way  For numeric data, ascending order is the most common  Lots of techniques for sorting  These techniques vary in performance both with runtime and usage of extra memory

 Given a sequence of numbers, it compares adjacent numbers and swap them if necessary  Repeats the above procedure until all numbers are in right place

Pick 4, compare with 10

Pick 10, compare with 9 Need to swap

Pick 10, compare with 6 Need to swap

Pick 10, compare with -1

Notice, that 10 is at the right position Now, repeat from the beginning

Compare 1 st element with 2 nd element

Compare 2nd element with 3rd element Swap needed

Compare 3 rd element with 4 th element Swap needed

Now, do we need the compare 4 th with the 5 th ? We already know 5 th element is the largest. This implies, what we have as the 4 th element, it must be the second largest, and is already in the correct place.

Now, repeat from the beginning again. But remember, we only need to go up to 3 rd this time.

 1 st iteration places the largest number in the correct place  2 nd iteration places the second largest number in the correct place  …..  ….  i-th iteration places the i-th largest number in the correct place

#include  #define ARR_SIZE 8  int main(void)  {  int intarr[ARR_SIZE] = {23, 4, 12, 8, 22, 1, 54, 9}, i, j, tmp;   for(i = 0; i<ARR_SIZE-1; i++)  {  for(j = 0; j<ARR_SIZE-i-1; j++)  { if(intarr[j]>intarr[j+1])  {  tmp = intarr[j];  intarr[j] = intarr[j+1];  intarr[j+1] = tmp;  } }  }  printf("The array sorted by Bubble Sort: ");  for(i = 0; i< ARR_SIZE; i++)  printf("%d ", intarr[i]);  return 0;  }