844. 比较含退格的字符串

Author: chenpengcode

str/844_backspaceCompare.py

@@ -0,0 +1,51 @@
+class Solution:
+    def backspaceCompare(self, S: str, T: str) -> bool:
+        def handle(s: str):
+            res = list()
+            for ch in s:
+                if ch != '#':
+                    res.append(ch)
+                elif res:
+                    res.pop()
+            return "".join(res)
+
+        return handle(S) == handle(T)
+
+    def backspaceCompare_1(self, S: str, T: str) -> bool:
+        i, j = len(S) - 1, len(T) - 1
+        skip0 = skip1 = 0
+
+        while i >= 0 or j >= 0:
+            while i >= 0:
+                if S[i] == '#':
+                    skip0 += 1
+                    i -= 1
+                elif skip0 > 0:
+                    i -= 1
+                    skip0 -= 1
+                else:
+                    break
+            while j >= 0:
+                if T[j] == '#':
+                    skip1 += 1
+                    j -= 1
+                elif skip1 > 0:
+                    j -= 1
+                    skip1 -= 1
+                else:
+                    break
+            if i >= 0 and j >= 0:
+                if S[i] != T[j]:
+                    return False
+            elif i >= 0 or j >= 0:
+                return False
+            i -= 1
+            j -= 1
+        return True
+
+
+if __name__ == '__main__':
+    S = "ab#c"
+    T = "ad#c"
+    solution = Solution()
+    print(solution.backspaceCompare_1(S, T))