add 221

Author: luliyucoordinate

README.md

@@ -194,7 +194,7 @@ LeetCode
 |0216|[Combination Sum III](https://leetcode.com/problems/combination-sum-iii/) | c | [c++](./src/0216-Combination-Sum-III/0216.cpp) |[python](./src/0216-Combination-Sum-III/0216.py)|||Medium|
 |0217|[Contains Duplicate](https://leetcode.com/problems/contains-duplicate/) | c | [c++](./src/0217-Contains-Duplicate/0217.cpp) |[python](./src/0217-Contains-Duplicate/0217.py)|||Easy|
 |0219|[Contains Duplicate II](https://leetcode.com/problems/contains-duplicate-ii/) | c | [c++](./src/0219-Contains-Duplicate-II/0219.cpp) |[python](./src/0219-Contains-Duplicate-II/0219.py)|||Easy|
-|0221|[Maximal Square](https://leetcode.com/problems/maximal-square/) | c | [c++](./src/0221-Maximal-Square/0221.cpp) |[python](./src/0221-Maximal-Square/0221.py)|||Medium|
+|0221|[Maximal Square](https://leetcode.com/problems/maximal-square/) | c | [c++](./src/0221-Maximal-Square/0221.cpp) |[python](./src/0221-Maximal-Square/0221.py)|[go](./src/0221-Maximal-Square/0221.go)|[js](./src/0221-Maximal-Square/0221.js)|Medium|
 |0222|[Count Complete Tree Nodes](https://leetcode.com/problems/count-complete-tree-nodes/) | c | [c++](./src/0222-Count-Complete-Tree-Nodes/0222.cpp) |[python](./src/0222-Count-Complete-Tree-Nodes/0222.py)|||Medium|
 |0223|[Rectangle Area](https://leetcode.com/problems/rectangle-area/) | c | [c++](./src/0223-Rectangle-Area/0223.cpp) |[python](./src/0223-Rectangle-Area/0223.py)|||Medium|
 |0226|[Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/) | c | [c++](./src/0226-Invert-Binary-Tree/0226.cpp) |[python](./src/0226-Invert-Binary-Tree/0226.py)|||Easy|

src/0221-Maximal-Square/0221.cpp

@@ -0,0 +1,20 @@
+class Solution 
+{
+public:
+    int maximalSquare(vector<vector<char>>& matrix) 
+    {
+        if (matrix.empty()) return 0;
+        int res = 0, r = matrix.size(), c = matrix[0].size();
+        int mem[r][c] = {};
+        for (int i = 0; i < r; ++i)
+        {
+            for (int j = 0; j < c; ++j)
+            {
+                if (!i or !j or matrix[i][j] == '0') mem[i][j] = matrix[i][j] - '0';
+                else mem[i][j] = min({mem[i-1][j], mem[i][j-1], mem[i-1][j-1]}) + 1;
+                res = max(res, mem[i][j]);
+            }
+        }
+        return res * res;
+    }
+};

src/0221-Maximal-Square/0221.go

@@ -0,0 +1,35 @@
+func maximalSquare(matrix [][]byte) int {
+    if len(matrix) == 0 {
+        return 0
+    }
+    res, r, c := 0, len(matrix), len(matrix[0])
+    mem := make([][]int, r)
+    for i := 0; i < r; i++ {
+        mem[i] = make([]int, c)
+    }
+    for i := 0; i < r; i++ {
+        for j := 0; j < c; j++ {
+            if i == 0 || j == 0 || matrix[i][j] == '0' {
+                mem[i][j] = int(matrix[i][j]) - int('0')
+            } else {
+                mem[i][j] = min(mem[i][j-1], min(mem[i-1][j], mem[i-1][j-1])) + 1
+            }
+            res = max(res, mem[i][j])
+        }
+    }
+    return res * res
+}
+
+func min(a, b int) int {
+    if a < b {
+        return a
+    }
+    return b
+}
+
+func max(a, b int) int {
+    if a > b {
+        return a
+    }
+    return b
+}

src/0221-Maximal-Square/0221.js

@@ -0,0 +1,19 @@
+var maximalSquare = function(matrix) {
+    if (!matrix.length) return 0;
+    let res = 0, r = matrix.length, c = matrix[0].length;
+    let mem = new Array(r);
+    for (let i = 0; i < r; ++i) {
+        mem[i] = new Array(c);
+        mem[i].fill(0);
+    }
+    for (let i = 0; i < r; ++i)
+    {
+        for (let j = 0; j < c; ++j)
+        {
+            if (!i || !j || matrix[i][j] == '0') mem[i][j] = Number(matrix[i][j]);
+            else mem[i][j] = Math.min(Math.min(mem[i-1][j], mem[i][j-1]), mem[i-1][j-1]) + 1;
+            res = Math.max(res, mem[i][j]);
+        }
+    }
+    return res * res;
+};

src/0221-Maximal-Square/0221.py

@@ -0,0 +1,16 @@
+class Solution:
+    def maximalSquare(self, matrix: List[List[str]]) -> int:
+        if not matrix:
+            return 0
+            
+        res, r, c = 0, len(matrix), len(matrix[0])
+        mem = [[0]*c for _ in range(r)]
+
+        for i in range(r):
+            for j in range(c):
+                if not i or not j or matrix[i][j] == '0':
+                    mem[i][j] = int(matrix[i][j])
+                else:
+                    mem[i][j] = min(mem[i-1][j], mem[i-1][j-1], mem[i][j-1]) + 1
+                res = max(res, mem[i][j])
+        return res**2