Print all permutations of $k$ elements from the positive integers $1,2,3,\ldots,n$.
A permutation is a way of selecting items from a larger group, where the order matters.
### Input
- One line containing two integers $n$ and $k$.
### Output
- Each line contains $k$ integers representing a permutation. The output should follow dictionary order.
### Constraints
- $1 \le k < n \le 7$.
### Example
Input:
```
3 2
```
Output:
```
1 2
1 3
2 1
2 3
3 1
3 2
```
