class Solution
{
    public:
        bool areAlmostEqual(string s1, string s2)
        {
            if (s1 == s2) return true;	
            vector<int> a;	
            for (int i = 0; i < (int) s2.size(); i++)	
            {
                if (s1[i] != s2[i]) a.push_back(i);	
            }
            if (a.size() == 2)	 
            {
                int x = a[0], y = a[1];
                if (s1[x] == s2[y] && s1[y] == s2[x])
                    return true;
            }
            return false;
        }
};