70 lines
1.8 KiB
C
70 lines
1.8 KiB
C
/* Program to demonstrate non recursive merge sort */
|
|
|
|
#include <stdio.h>
|
|
#include <conio.h>
|
|
|
|
void mergesort(int x[ ], int n) ;
|
|
void show(int x[ ], int n) ;
|
|
|
|
void main()
|
|
{
|
|
int i, n, x[20] ;
|
|
clrscr() ;
|
|
printf("Enter the number of elements: ") ;
|
|
scanf("%d",&n) ;
|
|
printf("Enter the elements:\n") ;
|
|
for(i=0 ; i<n ; i++)
|
|
scanf("%d",&x[i]) ;
|
|
mergesort(x,n) ;
|
|
printf("Sorted array is as shown:\n") ;
|
|
for(i=0 ; i<n ; i++)
|
|
printf("%d ", x[i]) ;
|
|
getch() ;
|
|
}
|
|
|
|
void mergesort(int x[ ], int n)
|
|
{
|
|
int temp[50], i, j, k, lb1, lb2, ub1, ub2, size ;
|
|
size=1 ;
|
|
while(size<n)
|
|
{
|
|
lb1=0 ;
|
|
k=0 ;
|
|
while(lb1+size<n)
|
|
{
|
|
lb2=lb1+size ;
|
|
ub1=lb2-1 ;
|
|
if(ub1+size<n)
|
|
ub2=ub1+size ;
|
|
else
|
|
ub2=n-1 ;
|
|
i=lb1 ;
|
|
j=lb2 ;
|
|
while(i<=ub1&&j<=ub2)
|
|
if(x[i]<x[j])
|
|
temp[k++]=x[i++] ;
|
|
else
|
|
temp[k++]=x[j++] ;
|
|
while(i<=ub1)
|
|
temp[k++]=x[i++] ;
|
|
while(j<=ub2)
|
|
temp[k++]=x[j++] ;
|
|
lb1=ub2+1 ;
|
|
}
|
|
for(i=0 ; i<=ub2 ; i++)
|
|
x[i]=temp[i] ;
|
|
size=size*2 ;
|
|
show(x,n) ;
|
|
}
|
|
}
|
|
|
|
void show(int x[ ], int n)
|
|
{
|
|
int i ;
|
|
for(i=0 ; i<n ; i++)
|
|
printf("%d ", x[i]) ;
|
|
printf("\n\n") ;
|
|
}
|
|
|
|
|
|
/* The method show() is optional. It is written to show output of each pass. It may not be written in theory exam. It is required only in practical exams */ |