Leetcode 1428

Coding question asked in Facebook interviews.

'''
0000000011    1. start from top right corner
0000011111 => 2. keep moving left until reaches a 0
0000000011    3. move down and repeat step 2
0011111111
0000000011

(0, 9) => (0, 7) => (1, 7) => (1, 4) => (2, 4) => (3, 4) => (3, 1)
'''
class Solution:
    def leftMostColumnWithOne(self, binaryMatrix: 'BinaryMatrix') -> int:
        # BinaryMatrix.get(row, col) => value
        # BinaryMatrix.dimensions() => [rows, cols]
        rows, cols = binaryMatrix.dimensions()
        currentR, currentC = 0, cols - 1
        while currentR < rows and currentC >= 0:
            if binaryMatrix.get(currentR, currentC) == 0:
                currentR += 1
            else:
                currentC -= 1
        
        if currentC == cols - 1:
            return -1
        
        return currentC + 1