Spiral Matrix III

lc885.py

@@ -0,0 +1,28 @@
+def spiralMatrixIII(R, C, r0, c0):
+    """
+    :type R: int
+    :type C: int
+    :type r0: int
+    :type c0: int
+    :rtype: List[List[int]]
+    """
+
+    directions=[(0,1),(1,0),(0,-1),(-1,0)]
+    d=0
+    steps=1
+    res=[(r0,c0)]
+    squares=1
+
+    while squares<R*C:
+        # steps=int(squares**0.5) # 太麻烦
+        for i in range(steps):
+            r0,c0=r0+directions[d][0],c0+directions[d][1]
+            if 0<=r0<R and 0<=c0<C:
+                squares+=1
+                res.append((r0,c0))
+        d=(d+1)%4
+        steps+=((d+1)%2)
+    return res
+
+R = 5; C = 6; r0 = 1; c0 = 4
+print(spiralMatrixIII(R, C, r0, c0))