进行了分类

Author: princewen

easy/167_Two Sum II - Input array is sorted.py renamed to easy/dict保存/167_Two Sum II - Input array is sorted.py

@@ -0,0 +1,87 @@
+"""
+
+Given two strings s and t, determine if they are isomorphic.
+
+Two strings are isomorphic if the characters in s can be replaced to get t.
+
+All occurrences of a character must be replaced with another character while preserving the order of characters. No two characters may map to the same character but a character may map to itself.
+
+For example,
+Given "egg", "add", return true.
+
+Given "foo", "bar", return false.
+
+Given "paper", "title", return true.
+
+"""
+
+"""my solution
+用一个字典保存
+"""
+
+class Solution(object):
+    def isIsomorphic(self, s, t):
+        """
+        :type s: str
+        :type t: str
+        :rtype: bool
+        """
+        if len(s)!=len(t):
+            return False
+        res = dict()
+        for i in range(0,len(s)):
+            if s[i] in res.keys():
+                if res[s[i]] == t[i]:
+                    continue
+                else:
+                    return False
+            else:
+                if t[i] in res.values():
+                    return False
+                else:
+                    res[s[i]] = t[i]
+        return True
+
+"""other solutions
+"""
+
+
+def isIsomorphic1(self, s, t):
+    d1, d2 = {}, {}
+    for i, val in enumerate(s):
+        d1[val] = d1.get(val, []) + [i]
+    for i, val in enumerate(t):
+        d2[val] = d2.get(val, []) + [i]
+    return sorted(d1.values()) == sorted(d2.values())
+
+
+def isIsomorphic2(self, s, t):
+    d1, d2 = [[] for _ in xrange(256)], [[] for _ in xrange(256)]
+    for i, val in enumerate(s):
+        d1[ord(val)].append(i)
+    for i, val in enumerate(t):
+        d2[ord(val)].append(i)
+    return sorted(d1) == sorted(d2)
+
+"""巧妙利用zip的原理"""
+def isIsomorphic3(self, s, t):
+    return len(set(zip(s, t))) == len(set(s)) == len(set(t))
+
+
+def isIsomorphic4(self, s, t):
+    return [s.find(i) for i in s] == [t.find(j) for j in t]
+
+
+def isIsomorphic5(self, s, t):
+    return map(s.find, s) == map(t.find, t)
+
+
+def isIsomorphic(self, s, t):
+    d1, d2 = [0 for _ in xrange(256)], [0 for _ in xrange(256)]
+    for i in xrange(len(s)):
+        if d1[ord(s[i])] != d2[ord(t[i])]:
+            return False
+        d1[ord(s[i])] = i + 1
+        d2[ord(t[i])] = i + 1
+    return True
+