@@ -49,27 +49,218 @@ N = 3
4949
5050<p >  ; </p >
5151
52- 5352## 解法
5453
5554<!-- 这里可写通用的实现逻辑 -->
5655
56+ "哈希表"实现。
57+ 5758<!-- tabs:start -->
5859
5960### ** Python3**
6061
6162<!-- 这里可写当前语言的特殊实现逻辑 -->
6263
6364``` python
64- 65+ class Solution :
66+ def findBlackPixel (self picture : List[List[str ]], target : int ) -> int :
67+ m, n = len (picture), len (picture[0 ])
68+ rows = [0 ] * m
69+ cols = collections.defaultdict(list )
70+ for i in range (m):
71+ for j in range (n):
72+ if picture[i][j] == ' B'
73+ rows[i] += 1
74+ cols[j].append(i)
75+ t = [[False ] * m for _ in range (m)]
76+ for i in range (m):
77+ for k in range (i, m):
78+ if i == k:
79+ t[i][k] = True
80+ else :
81+ t[i][k] = all ([picture[i][j] == picture[k][j] for j in range (n)])
82+ t[k][i] = t[i][k]
83+ res = 0
84+ for i in range (m):
85+ if rows[i] == target:
86+ for j in range (n):
87+ if len (cols[j]) == target and all ([t[i][k] for k in cols[j]]):
88+ res += 1
89+ return res
6590```
6691
6792### ** Java**
6893
6994<!-- 这里可写当前语言的特殊实现逻辑 -->
7095
7196``` java
97+ class Solution {
98+ public int findBlackPixel (char [][] picture , int target ) {
99+ int m = picture. length, n = picture[0 ]. length;
100+ int [] rows = new int [m];
101+ Map<Integer , List<Integer > > cols = new HashMap<> ();
102+ for (int i = 0 ; i < m; ++ i) {
103+ for (int j = 0 ; j < n; ++ j) {
104+ if (picture[i][j] == ' B'
105+ ++ rows[i];
106+ cols. computeIfAbsent(j, k - > new ArrayList<> ()). add(i);
107+ }
108+ }
109+ }
110+ boolean [][] t = new boolean [m][m];
111+ for (int i = 0 ; i < m; ++ i) {
112+ for (int k = i; k < m; ++ k) {
113+ t[i][k] = i == k || all(picture[i], picture[k]);
114+ t[k][i] = t[i][k];
115+ }
116+ }
117+ int res = 0 ;
118+ for (int i = 0 ; i < m; ++ i) {
119+ if (rows[i] == target) {
120+ for (int j = 0 ; j < n; ++ j) {
121+ List<Integer > col = cols. get(j);
122+ if (col != null && col. size() == target) {
123+ boolean check = true ;
124+ for (int k : col) {
125+ check = check && t[i][k];
126+ }
127+ if (check) {
128+ ++ res;
129+ }
130+ }
131+ }
132+ }
133+ }
134+ return res;
135+ }
136+ 137+ private boolean all (char [] row1 , char [] row2 ) {
138+ int n = row1. length;
139+ for (int j = 0 ; j < n; ++ j) {
140+ if (row1[j] != row2[j]) {
141+ return false ;
142+ }
143+ }
144+ return true ;
145+ }
146+ }
147+ ```
148+ 149+ ### ** C++**
150+ 151+ ``` cpp
152+ class Solution {
153+ public:
154+ int findBlackPixel(vector<vector<char >>& picture, int target) {
155+ int m = picture.size(), n = picture[ 0] .size();
156+ vector<int > rows(m);
157+ unordered_map<int, vector<int >> cols;
158+ for (int i = 0; i < m; ++i)
159+ {
160+ for (int j = 0; j < n; ++j)
161+ {
162+ if (picture[ i] [ j ] == 'B')
163+ {
164+ ++rows[ i] ;
165+ cols[ j] .push_back(i);
166+ }
167+ }
168+ }
169+ vector<vector<bool >> t(m, vector<bool >(m, false));
170+ for (int i = 0; i < m; ++i)
171+ {
172+ for (int k = i; k < m; ++k)
173+ {
174+ t[ i] [ k ] = i == k || all(picture[ i] , picture[ k] );
175+ t[ k] [ i ] = t[ i] [ k ] ;
176+ }
177+ }
178+ int res = 0;
179+ for (int i = 0; i < m; ++i)
180+ {
181+ if (rows[ i] == target)
182+ {
183+ for (int j = 0; j < n; ++j)
184+ {
185+ if (cols[ j] .size() == target)
186+ {
187+ bool check = true;
188+ for (int k : cols[ j] ) check = check && t[ i] [ k ] ;
189+ if (check) ++res;
190+ }
191+ }
192+ }
193+ }
194+ return res;
195+ }
196+ 197+ bool all(vector<char>& row1, vector<char>& row2) {
198+ int n = row1.size();
199+ for (int j = 0; j < n; ++j)
200+ if (row1[j] != row2[j]) return false;
201+ return true;
202+ }
203+ };
204+ ```
205+ 206+ ### ** Go**
207+ 208+ ``` go
209+ func findBlackPixel (picture [][]byte , target int ) int {
210+ m , n := len (picture), len (picture[0 ])
211+ rows := make ([]int , m)
212+ cols := make (map [int ][]int )
213+ for i := 0 ; i < m; i++ {
214+ for j := 0 ; j < n; j++ {
215+ if picture[i][j] == ' B'
216+ rows[i]++
217+ cols[j] = append (cols[j], i)
218+ }
219+ }
220+ }
221+ t := make ([][]bool , m)
222+ for i := 0 ; i < m; i++ {
223+ t[i] = make ([]bool , m)
224+ }
225+ for i := 0 ; i < m; i++ {
226+ for k := i; k < m; k++ {
227+ if i == k {
228+ t[i][k] = true
229+ } else {
230+ t[i][k] = all (picture[i], picture[k])
231+ }
232+ t[k][i] = t[i][k]
233+ }
234+ }
235+ res := 0
236+ for i := 0 ; i < m; i++ {
237+ if rows[i] == target {
238+ for j := 0 ; j < n; j++ {
239+ col , ok := cols[j]
240+ if ok && len (col) == target {
241+ check := true
242+ for _ , k := range col {
243+ check = check && t[i][k]
244+ }
245+ if check {
246+ res++
247+ }
248+ }
249+ }
250+ }
251+ }
252+ return res
253+ }
72254
255+ func all (row1 , row2 []byte ) bool {
256+ n := len (row1)
257+ for i := 0 ; i < n; i++ {
258+ if row1[i] != row2[i] {
259+ return false
260+ }
261+ }
262+ return true
263+ }
73264```
74265
75266### ** ...**
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