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30+ "source" : [
31+ " 剑指 Offer 04. 二维数组中的查找\n "
32+ " > **美团面试题**\n "
33+ " \n "
34+ " 在一个 $n * m$ 的二维数组中,每一行都按照从左到右递增的顺序排序,每一列都按照从上到下递增的顺序排序。请完成一个高效的函数,输入这样的一个二维数组和一个整数,判断数组中是否含有该整数。\n "
35+ " \n "
36+ " 示例: \n "
37+ " 现有矩阵 `matrix` 如下:\n "
38+ " ```\n "
39+ " [\n "
40+ " [1, 4, 7, 11, 15],\n "
41+ " [2, 5, 8, 12, 19],\n "
42+ " [3, 6, 9, 16, 22],\n "
43+ " [10, 13, 14, 17, 24],\n "
44+ " [18, 21, 23, 26, 30]\n "
45+ " ]\n "
46+ " ```\n "
47+ " - 给定 `target = 5`,返回 `true`\n "
48+ " - 给定 `target = 20`,返回 `false`\n "
49+ " \n "
50+ " **限制:** \n "
51+ " - 0ドル \\ leq n \\ leq 1000$\n "
52+ " - 0ドル \\ leq m \\ leq 1000$\n "
53+ " \n "
54+ " 来源:力扣(LeetCode) \n "
55+ " 链接:https://leetcode-cn.com/problems/er-wei-shu-zu-zhong-de-cha-zhao-lcof \n "
56+ " 著作权归领扣网络所有。商业转载请联系官方授权,非商业转载请注明出处。"
57+ ],
58+ "cell_type" : " markdown"
59+ "metadata" : {}
60+ },
61+ {
62+ "cell_type" : " code"
63+ "execution_count" : 2 ,
64+ "metadata" : {},
65+ "outputs" : [],
66+ "source" : [
67+ " from typing import List\n "
68+ " class Solution:\n "
69+ " def findNumberIn2DArray(self, matrix: List[List[int]], target: int) -> bool:\n "
70+ " m = len(matrix) # 行数\n "
71+ " if m == 0: return False\n "
72+ " n = len(matrix[0]) # 列数\n "
73+ " i, j = m-1, 0 # 从左下角开始二分查找\n "
74+ " while i >= 0 and j < n:\n "
75+ " if matrix[i][j] < target:\n "
76+ " j += 1\n "
77+ " elif matrix[i][j] > target:\n "
78+ " i -= 1\n "
79+ " else:\n "
80+ " return True\n "
81+ " return False"
82+ ]
83+ },
84+ {
85+ "cell_type" : " code"
86+ "execution_count" : 3 ,
87+ "metadata" : {},
88+ "outputs" : [],
89+ "source" : [
90+ " # 测试\n "
91+ " matrix = [\n "
92+ " [1, 4, 7, 11, 15],\n "
93+ " [2, 5, 8, 12, 19],\n "
94+ " [3, 6, 9, 16, 22],\n "
95+ " [10, 13, 14, 17, 24],\n "
96+ " [18, 21, 23, 26, 30]\n "
97+ " ]"
98+ ]
99+ },
100+ {
101+ "cell_type" : " code"
102+ "execution_count" : 4 ,
103+ "metadata" : {},
104+ "outputs" : [
105+ {
106+ "output_type" : " execute_result"
107+ "data" : {
108+ "text/plain" : [
109+ " True"
110+ ]
111+ },
112+ "metadata" : {},
113+ "execution_count" : 4
114+ }
115+ ],
116+ "source" : [
117+ " mat = Solution()\n "
118+ " mat.findNumberIn2DArray(matrix, target=5)"
119+ ]
120+ },
121+ {
122+ "cell_type" : " code"
123+ "execution_count" : 5 ,
124+ "metadata" : {},
125+ "outputs" : [
126+ {
127+ "output_type" : " execute_result"
128+ "data" : {
129+ "text/plain" : [
130+ " False"
131+ ]
132+ },
133+ "metadata" : {},
134+ "execution_count" : 5
135+ }
136+ ],
137+ "source" : [
138+ " mat.findNumberIn2DArray(matrix, target=20)"
139+ ]
140+ }
141+ ]
142+ }
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