1957. Delete Characters to Make Fancy String

class Solution {
public:
    string makeFancyString(string s) {
        if(s.size()<3)return s;
        int j=2;
        for(int i=2;i<s.size();i++){
            if(s[i]!=s[j-1] ||s[i]!=s[j-2]){
                s[j++]=s[i];
            }
        }
        s.resize(j);
        return s;
    }
};