Pretty JSON

Pretty JSON:-
Difficulty = Medium

#include <bits/stdc++.h> 
vector<string> prettyJSON(string &str) {
    int n=str.size(),space=0;
    vector<string> ans;
    string s="";
    for(int i=0;i<n;i++){
        if(str[i]=='[' || str[i]=='{'){
            if(s!=""){
                string aa="";
                for(int j=1;j<=space;j++) aa+="\t";
                ans.push_back(aa+s);
            }
            string aa="";
            for(int j=1;j<=space;j++) aa+="\t";
            ans.push_back(aa+str[i]);
            space++;
            s="";
        }
        else if(str[i]==','){
            s+=str[i];
            string aa="";
            for(int j=1;j<=space;j++) aa+="\t";
            ans.push_back(aa+s);
            s="";
        }
        else if(str[i]==']'|| str[i]=='}'){
            if(s!=""){
                string aa="";
                for(int j=1;j<=space;j++) aa+="\t";
                ans.push_back(aa+s);
            }
            space--;
            s=str[i];
        }
        else s+=str[i];
    }
    ans.push_back(s);
    return ans;
    // Write your code here.
}