LeetCode:Word Pattern

Word Pattern

Total Accepted: 21299 Total
Submissions: 77656 Difficulty: Easy

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.
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Word Pattern II

code:

class Solution {
public:
    bool wordPattern(string pattern, string str) {
        map<char, int> cmap;
        map<string, int> smap;
        int n = pattern.size();
        istringstream in(str);

        int i=0;
        for(string word;in>>word;i++)
        {
            if(cmap[pattern[i]] != smap[word]) return false;
            cmap[pattern[i]] = smap[word] = i+1;
        }
        return i==n;
    }
};