290. Word Pattern

/*Given a pattern and a string str, find if str follows the same pattern.Here follow means a full match, such that there is a bijection between a letter in pattern and a non-empty word in str.Examples:pattern = "abba", str = "dog cat cat dog" should return true.pattern = "abba", str = "dog cat cat fish" should return false.pattern = "aaaa", str = "dog cat cat dog" should return false.pattern = "abba", str = "dog dog dog dog" should return false.Notes:You may assume pattern contains only lowercase letters, and str contains lowercase letters separated by a single space.使用两个hash表，其键为相应的字符与word，其值存储相同的数字，当相同的字符在此出现时，则相应位置上的word的键值如果与其字符的键值相同，则格式一样，否则格式不同。*/#include <iostream>#include <vector>#include <unordered_map>#include <string>using namespace std;class Solution {public:    bool wordPattern(string pattern, string str) {        vector<string> tmp;        int i=0;        for(int j=0;i<str.size() && j<=str.size();j++)//split str             if(str[j]==' ' || j==str.size())            {                tmp.push_back(str.substr(i,j-i));                i=j+1;            }                   if(pattern.size()!=tmp.size()) return false;        unordered_map<char,int> mp;        unordered_map<string,int> ms;        i=0;        for(;i<pattern.size();i++)        {            if(i!=0 && mp[pattern[i]]!=ms[tmp[i]])                return false;            mp[pattern[i]]=i+1;            ms[tmp[i]]=i+1;        }        return mp[pattern[i-1]]==ms[tmp[i-1]];    }};int main(){    Solution mys;    string pattern="aab";    string str="dog dog dog";    cout<<mys.wordPattern(pattern,str)<<endl;    return 0;}