Without using extra space place all zeroes to left and 1's to right from an array of Zero's and 1's as below 011001 ans. 000111

#include<iostream.h>

#include<conio.h>

void main()

{

      clrscr();

      int a[]={0,1,1,0,0,1};

      int n=sizeof(a)/sizeof(int);

      int i=0,j=n-1;

      while(i<j)

      {

            if(a[i]==0)

                  i++;

            if(a[j]==1)

                  j--;

            if(a[i]==1 && a[j]==0)

            {

                  a[i]=0;

                  a[j]=1;

                  i++;

                  j--;

            }

      }

      for(i=0;i<n;i++)

            cout<<" "<<a[i];

      getch();

}