A thermal camera reports an R-by-C grid of integer temperatures. The readings are calibrated so that every row is sorted in non-increasing order from left to right, and every column is sorted in non-increasing order from top to bottom (so the warmest reading is at the top-left and the coldest at the bottom-right).
Count how many readings are strictly below zero (negative).
Input format
Line 1: two integers R and C.
Next R lines: each contains C space-separated integers, forming a matrix that is non-increasing along every row and down every column.
Output format
A single integer: the number of negative readings.
Constraints
- 1 <= R, C <= 200
- -1000000000 <= each reading <= 1000000000
- Every row is non-increasing left to right; every column is non-increasing top to bottom.