public static void sink(int[] a,int k)
	{
		
		while(2*k<=a.length-1)
		{
			int i=2*k;
			
			if(i<a.length-1 && a[i]<a[i+1])
				i=i+1;

			if(a[k]>a[i])
				break;
			
			int tmp=a[k];
			a[k]=a[i];
			a[i]=tmp;
			
			k=i;
			
		}
		
		
		
	}