从左下角开始,贪心搜索

# -*- coding:utf-8 -*-

class Solution:
    def findElement(self, mat, n, m, x):
        # write code here
        i, j = n-1, 0
        while i >= 0 and i < n and j >= 0 and j < m:
            if mat[i][j] > x:
                i = i-1
            elif mat[i][j] < x:
                j = j+1
            else:
                return [i, j]