add 859 array

Author: MatNoble

LeetCodeSolutions/859.py

@@ -0,0 +1,36 @@
+#==================================================
+#==>      Title: 859. 亲密字符串
+#==>     Author: Zhang zhen                   
+#==>      Email: hustmatnoble.gmail.com
+#==>     GitHub: https://github.com/MatNoble
+#==>       Date: 2/1/2021
+#==================================================
+
+"""
+https://leetcode-cn.com/problems/buddy-strings/
+"""
+
+class Solution:
+    def buddyStrings(self, A: str, B: str) -> bool:
+        n, m = len(A), len(B)
+        if n != m: return False
+        if A == B:
+            C = set()
+            for a in A:
+                if a in C: return True
+                C.add(a)
+            return False
+        else:
+            C = []
+            for i in range(n):
+                if A[i] != B[i]:
+                    C.append([A[i], B[i]])
+                if len(C) >=3: return False
+            return len(C) == 2 and C[0] == C[-1][::-1]
+
+mat = Solution()
+A = 'acb'
+B = 'abc'
+A = 'aa'
+B = 'aa'
+mat.buddyStrings(A, B)