Can someone explain the misbehaviour of this code

[jinnejeevansai]

I was trying to solve a problem then i observed a misbehaviour in my code,it is asking for input continuosly how much input i give and this is only happening for some particular inputs.

#include<stdio.h>
  void fun(int a[],int n,int k)
	{
    	int i,j,t;
    	int b[1000];
     	for(i=0;i<n;i++)
		{
			b[i]=1;
			while(a[i]!=1&&a[i]!=0)
			{
				if(a[i]%2==1)
				b[i]++;
				a[i]=a[i]/2;
			}
                     if(a[i]==0)
                     b[i]=0;
		}
		for(i=0;i<k;i++)
		{
			int max=i;
			for(j=i;j<n-1;j++)
			{
				if(b[j]>b[max])
				{
					max=j;
				}
			}
			t=a[i];
			a[i]=a[max];
			a[max]=t;
			t=b[i];
			b[i]=b[max];
			b[max]=t;
		printf("%d",a[i]);
		}
	}
	int main()
	{ 
		int t,n,k,i,j,a[1000];
        scanf("%d",&t);
        for(i=0;i<t;i++)
        {
            scanf("%d %d",&n,&k);
        	for(j=0;j<n;j++)
        	{
        	     scanf("%d",&a[j]);
        	}
        	fun(a,n,k);
        }
    }

[donbock]

I suggest you add code after lines 40 and 43 to test the entered values of t, n, and k to make sure they make sense.

What should happen if a[i] is negative? Should the tests on lines 9 and 11 also check for -1?