Merge sort is a sorting algorithm that uses a divide and conquer technique. It divides an array into halves, recursively sorts each half, and then merges the sorted halves into a single sorted array. John Von Neumann developed merge sort in 1945 for the EDVAC computer. Merge sort has a time complexity of O(n log n), making it one of the most efficient sorting algorithms.

1. Merge Sort
Presentation By :Showrov Ahmed
ID:161-35-140
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2. In the Beginning…
In the Beginning…
John Von Neumann
(1903-1957)
•Stored program
•Developed merge
sort for EDVAC in
1945
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3. •Merge sort is a sorting technique based on divide and
conquer technique. With worst-case time complexity
being Ο(n log n), it is one of the most respected
algorithms. Merge sort first divides the array into equal
halves and then combines them in a sorted manner.
What is Merge Sort?
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4. Merge Sort Example
10 5 2 1 9 6 4 20
10 5 2 1 9 6 4 20
10 5 2 1 9 6 4 20
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5. 10 5 2 1 9 6 4 20
5 10 1 2 6 9 4 20
1 2 5 10 4 6 9 20
1 2 4 5 6 9 10 20
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6. Main part of Code:
int mergesort (int a[], int low, int high)
{ int mid;
if
{mid =(low+high)/2;
mergesort(a,low,mid);
mergesort(a,mid+1,high);
merge(a, low, high);
}
return (0);
}
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7. About Merge Sort
>Merge sort follows recursive algorithom………………………….
>We divide the array into halves till the sub array has only 1
element.
>Major work is done in merging the sub arrays……………………..
>We need an extra temporary array of the same size as the input
array for merging..
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