SORTING ALGORITHMS

Engr. Shaheer Ahmed

ALGO - INSERTION SORT (N, A)A : ArrayN : Length of Array A[]

Start AlgoFor i:=1 to N-1 do value := A[i] j := i-1 while j >= 0 and A[j] > value do A[j+1] := A[j] j := j-1 endwhile A[j+1] = value EndforEnd Algo

Program – Insertion Sort#include<iostream>using namespace std;

main(){int A[6] = {6,5,4,3,2,1};int N=6;int i,j,val;

for(i=1;i<N;i++) { val=A[i]; j=i-1;

while(j>=0 && A[j]>val) { A[j+1]=A[j]; j=j-1; } A[j+1]=val; }cout<<endl;

for(int i = 0 ; i<N ; i++)cout<<A[i]<<" "; system("pause");}

Insertion Sort

Worst case analysis of Insertion Sort

Apply Insertion Sort on the following Data: 7,6,5,4,3,2,1

Selection Sort

Program – Selection Sort#include<iostream>using namespace std;

main(){int A[6] = {5,2,6,4,3,1};int N=6;int i,sel=0,min,index,swap=0, temp;

//Find smallest number and swap with selected index with each iteration of outer loop

while(sel<N){min = A[sel];for(i = sel; i< N; i++){ if(A[i]<min) //if smaller number is found { min=A[i]; index=i; // save index of smaller number swap=1; // swapping required.. } }//swapping if(swap==1){A[sel] = A[sel] + A[index]; // a = a+bA[index] = A[sel] - A[index]; // b = a - bA[sel] = A[sel] - A[index]; // a = a-b}

sel++;swap=0;}

for(int i = 0 ; i<N ; i++)cout<<A[i]<<" ";

system("pause");}

Apply Selection Sort on the following Data:7,6,5,4,3,2,1

Worst case analysis of Selection Sort

Quick Sort15 20 35 10 25 55 50 45 40 30

3015 20 10 25 35 55 50 45 40

3015 20 2510 4535 40 50 55

15 2010 25 35 4540 50 55

10 15 20 25 30 35 40 45 50 55

30

MERGE SORT

15 , 20 , 35 , 10 , 25 , 55 , 50 , 45

15 20 10 35 25 55 45 50

10 15 20 35 25 45 50 55

10 15 20 25 35 45 50 55

GIVEN DATA