#1582

Special Positions in a Binary Matrix

newbie · 255 · lc easy +19 · verified · 72.6% accepted · 1,785 likes · top 82%

Description

Given an m x n binary matrix mat, return the count of special positions. A position (i, j) is special when mat[i][j] == 1 and every other element in row i and column j is 0.

Example 1:

Input: mat = [[1,0,0],[0,0,1],[1,0,0]]

Output: 1

Explanation: (1, 2) is a special position because mat[1][2] == 1 and all other elements in row 1 and column 2 are 0.

Example 2:

Input: mat = [[1,0,0],[0,1,0],[0,0,1]]

Output: 3

Explanation: (0, 0), (1, 1) and (2, 2) are special positions.

Code

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class Solution:
    def numSpecial(self, mat: List[List[int]]) -> int:

class Solution:
    def numSpecial(self, mat: List[List[int]]) -> int: