Check if string is rotated by two places

class Solution
{
    public:
    //Function to check if a string can be obtained by rotating
    //another string by exactly 2 places.
    bool isRotated(string str1, string str2)
    {
        // Your code here
        int n=str1.length();
        if(str1.length()!=str2.length()){
            return false;
        }
        if(str1.substr(2,n)+str1.substr(0,2)==str2 || str1.substr(n-2,n)+str1.substr(0,n-2)==str2){
            return true;
        }
        return false;
    }

};