QUICK SORT

Quick sort• Uses divide-and-conquer approach

• Divide: If S has at least two elements select a specific element x from S, called the pivot. Partition S into

– L storing elements in S less than x

– E storing elements in S equal to x

– G storing elements in S greater than or equal to x

• Recur: recursively sort sequences L and G

• Conquer: put elements in L, E and G back into S in order

GIVEN SERIES

5 3 8 9 1 7 0 2 6 4

SELECT THE PIVOT ELEMENT

P

5 3 8 9 1 7 0 2 6 4

P L R

ITERATION-1

5 3 8 9 1 7 0 2 6 4

SWAPE THE ELEMENTS

5 3 4 9 1 7 0 2 6 8

5 3 4 9 1 7 0 2 6 8

P L R

5 3 4 2 1 7 0 9 6 8

SWAP THE ELEMENTS

5 3 4 2 1 7 0 9 6 8

P L R

SWAP THE ELEMENTS

5 3 4 2 1 0 7 9 6 8

P R L

0 3 4 2 1 5 7 9 6 8

P > R > L

0 3 4 2 1 5 7 9 6 8

0 1 4 2 3 5 7 6 9 8

P L R P L R

0 3 4 2 1 5 7 9 6 8

ITERATION-2

SWAP THE ELEMENTS

0 1 4 2 3 5 6 7 9 8

P L R P L R

SWAP THE ELEMENTS

0 1 2 4 3 5 6 7 9 8

5 6 7 9 8 0 1 2 4 3

5 6 7 8 90 1 2 3 4

SWAP THE ELEMENTS

0 1 2 3 4 5 6 7 8 9