Generate Gray Code

Generate Gray Code

  October 25, 2017    

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 Idea is get graycode for n-1.
Reverse the retreived code and add to list
 and add 0 to previous list and 1 to reversed list as prefix.


Code:

  void generateCode(int n)
    {
if(n<=0)
return;
List<String> arr=new ArrayList<String>();
arr.add("0");
arr.add("1");
for(int i=2;i<=n;++i)
{
    for(int j=(1<<i-1)-1;j>=0;--j)
    {
        arr.add("1"+arr.get(j));
    }
    
    for(int j=0;j<(1<<i-1);++j)
    {
        String ftr="0"+arr.get(j);
        arr.remove(j);
        arr.add(j,ftr);
    }
   // System.out.println();
}

for(String st:arr)
System.out.print(st+" ");
    }