205. Isomorphic Strings; 290. Word Pattern

205. Isomorphic Strings
class Solution(object):
    def isIsomorphic(self, s, t):
        """
        :type s: str
        :type t: str
        :rtype: bool
        """
        mapping={}
        result = True
        for i in range(len(s)):
            if s[i] not in mapping:
                if t[i] in mapping.values():
                    result =  False
                    break
                else:
                    mapping[s[i]] = t[i]
            else:
                if mapping[s[i]]<>t[i]:
                    result = False
                    break
        return result



290. Word Pattern

class Solution(object):
    def wordPattern(self, pattern, str):
        """
        :type pattern: str
        :type str: str
        :rtype: bool
        """
        mapping={}
        result = True
        str_ls = str.split()
        if len(pattern)<>len(str_ls):
            result = False
        else:
            for i in range(len(pattern)):
                if pattern[i] not in mapping:
                    if str_ls[i] in mapping.values():
                        result =  False
                        break
                    else:
                        mapping[pattern[i]] = str_ls[i]
                else:
                    if mapping[pattern[i]]<>str_ls[i]:
                        result = False
                        break
        return result