[leetcode] Isomorphic Strings

Isomorphic Strings

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.

Note:
You may assume both s and t have the same length.

 

class Solution
{
private:
  int GetPos(string &s, char ch, int n)
  {
    for(int i=0; i<=n; ++i)
      if(s[i] == ch)
        return i;

    return 0;
  }

public:
  bool isIsomorphic(string s, string t)
  {
    int lens = s.size();
    int lent = t.size();

    if(lens != lent)
      return false;

    vector<int> temp;
    for(int i=0; i<lens; ++i)
      temp.push_back(GetPos(s, s[i], i));

    for(int i=0; i<lent; ++i)
      if(GetPos(t, t[i], i) != temp[i])
        return false;

    return true;
  }
};