Set of Points

Description:

Input:

The single line contains two integers n and m (3 ≤ m ≤ 100, m ≤ n ≤ 2m).

Output:

If there is no solution, print "-1". Otherwise, print n pairs of integers — the coordinates of points of any set with the convexity of m. The coordinates shouldn't exceed 10⁸ in their absolute value.

Sample Input:

4 3

Sample Output:

0 0
3 0
0 3
1 1

Sample Input:

6 3

Sample Output:

-1

Sample Input:

6 6

Sample Output:

10 0
-10 0
10 1
9 1
9 -1
0 -2

Sample Input:

7 4

Sample Output:

176166 6377
709276 539564
654734 174109
910147 434207
790497 366519
606663 21061
859328 886001