Orchard Row Median Height

An orchard is laid out as m rows of trees with n trees per row. Within each row the tree heights are listed in non-decreasing order (heights across different rows are unrelated to one another). The total number of trees, m * n, is guaranteed to be odd. Determine the median height when all m * n trees are considered together.

Input Format

• Line 1: two space-separated integers m and n.
• The next m lines each contain n space-separated integers: the heights of the trees in that row, listed in non-decreasing order.

Output Format

Print a single integer: the median height across all m * n trees.

Constraints

• 1 <= m, n <= 500
• m * n is odd
• 1 <= height <= 10^6
• Each of the m rows is individually sorted in non-decreasing order.

3 3
1 3 5
2 6 9
3 5 8

5

1 1
7

7