You calculated k as,

```
k=r-(n-(j+1));
```

You could have done,

```
k=1+(j+r)%n;
```

If you still face any problem,

Here’s the link to my code.

@harshitbhalla See,

It is obvious that the minimum value of j will be 2 i.e. String would be 111…so on,

so,we have **k=r+3-n;**

Given that,**1 ≤ r ≤n** implies **4-n ≤ k ≤ 3**

and it’s wrong as you know, **1 ≤ k ≤ n**.