The document discusses the merge sort algorithm. It uses a divide and conquer technique where the array is divided into sub-arrays which are then merged together to produce a sorted output array. The algorithm recursively splits the array in half until individual values remain, and then combines the sorted sub-arrays back together to form the fully sorted final array.

1. TOPIC :-
MERGE SORT

2. BASIC CONCEPT OF MERGE
SORT
I. Uses divide and conquer technique.
II. array is divided into sub-array.
III. Sub-arrays merged to get sorted result.

3. DIVIDE AND CONQUER
Divide and conquer method for algorithm
design:
• Divide: Large problem is divided into sub-problems
• Conquer: recursively solve the sub-problems
• Combine:
• Take the solutions to the sub-problems
• “merge” these solutions into final solution
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4. DRY RUN OF PROGRAM
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25. AT THE END SORTED
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26. MERGING FUNCTION
void merge ( int , int , int ) ;
void merge _ sort(int low , int high)
{
int mid;
if(low<high)
{
mid=( low + high)/2 ;
merge _ sort ( low , mid) ;
merge _ sort(mid+1,high);
merge ( low , mid , high) ;
}
}

27. IMPLEMENTATION

28. SUMMARY OF SORTING
ALGORITHMS
Algorithm Time Notes
selection-sort O(n2) in-place
slow (good for small inputs)
insertion-sort O(n2) in-place slow (good for small
inputs)
quick-sort O(n log n)
expected
in-place, randomized fastest
(good for large inputs)
merge-sort O (n log n) sequential data access fast
(good for huge inputs)

29. ANY QUESTION…