update

draft.py

@@ -1,2 +1,3 @@
-
+mat = [[False for _ in range(3)] for _ in range(3)]
+print(mat)
 

generat_matrix.py

@@ -1,25 +1,61 @@
 from typing import List
 
-def generateMatrix(n: int) -> List[List[int]]:
-    l, r, t, b = 0, n - 1, 0, n - 1
-    mat = [[0 for _ in range(n)] for _ in range(n)]
-    num, tar = 1, n * n
-    while num <= tar:
-        for i in range(l, r + 1):  # left to right
-            mat[t][i] = num
-            num += 1
-        t += 1
-        for i in range(t, b + 1):  # top to bottom
-            mat[i][r] = num
-            num += 1
-        r -= 1
-        for i in range(r, l - 1, -1):  # right to left
-            mat[b][i] = num
-            num += 1
-        b -= 1
-        for i in range(b, t - 1, -1):  # bottom to top
-            mat[i][l] = num
-            num += 1
-        l += 1
-    return mat
+# def generateMatrix(n: int) -> List[List[int]]:
+    # 法一
+    # l, r, t, b = 0, n - 1, 0, n - 1
+    # res = [[0 for _ in range(n)] for _ in range(n)]
+    # num, tar = 1, n * n
+    # while num <= tar:
+    #     for i in range(l, r + 1):  # left to right
+    #         res[t][i] = num
+    #         num += 1
+    #     t += 1
+    #     for i in range(t, b + 1):  # top to bottom
+    #         res[i][r] = num
+    #         num += 1
+    #     r -= 1
+    #     for i in range(r, l - 1, -1):  # right to left
+    #         res[b][i] = num
+    #         num += 1
+    #     b -= 1
+    #     for i in range(b, t - 1, -1):  # bottom to top
+    #         res[i][l] = num
+    #         num += 1
+    #     l += 1
+    # return res
+
+# 法二
+class Solution:
+    def generateMatrix(self, n: int) -> List[List[int]]:
+        tar = n * n
+        visit = set()
+        x, y = 0, -1
+        dx, dy = 0, 1
+        res = [[0 for _ in range(n)] for _ in range(n)]
+        for num in range(tar):
+            x, y = x + dx, y + dy
+            visit.add((x, y))
+            res[x][y] = num + 1
+            dx, dy = self.coor((x, y), (dx, dy), visit, n)
+        return res
+
+
+    def coor(self, coord, direct, visit, n):
+        x, y = coord
+        dx, dy = direct
+        if dx == 0 and dy == 1:
+            if y == n - 1 or (x, y + 1) in visit:
+                return (1, 0)
+        if dx == 1 and dy == 0:
+            if x == n - 1 or (x + 1, y) in visit:
+                return (0, -1)
+        if dx == 0 and dy == -1:
+            if y == 0 or (x, y - 1) in visit:
+                return (-1, 0)
+        if dx == -1 and dy == 0:
+            if (x - 1, y) in visit:
+                return (0, 1)
+        return (dx, dy)
+
+