When i run my program I get this as a run time error Segmentation Fault (SIGSEGV)

When I run my code I get runtime error .I am trying to run this on geeksforgeeks, if it has something to do with the error. It gives segmentation fault as an error.

Segmentation Fault (SIGSEGV)

Here is my code

#include<bits/stdc++.h>
using namespace std;

class Solution{

public:
    bool isPalindrome(string str,int start,int end){
        while(start<end){
            if(str[start]!=str[end]) return false;
            start++;
            end--;
        }
        return true;
    }
void solve(vector<string>& v,int &ans,string &str, int i){
    if(i==str.length()){
        if(v.size()<ans) ans=v.size();
        return;
    }
    
    for(int j=i;j<str.length();j++){
        if(isPalindrome(str,i,j)) {
            v.push_back(str.substr(i,j-i+1));
            solve(v,ans,str,i);
            v.pop_back();
        }
    }
}
int palindromicPartition(string str)
{
    vector<string> v;
    int ans = INT_MAX;
    solve(v,ans,str,0);
    return ans-1;
}
};

int main(){
int t;
cin>>t;
while(t--){
    string str;
    cin>>str;
    solution ob;
    cout<<ob.palindromicPartition(str)<<"\n";
   }
return 0;
}