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Finding the mother node of a graph

#include<bits/stdc++.h>
using namespace std;
class graph
{
    int v;
    list<int> *adj;
public:
    graph(int v)
    {
        this->v=v;
        adj=new list<int>[v];
    }
    void add_edge(int v,int w)
    {
        adj[v].push_back(w);
    }
    void dfs(int start,bool visited[]);
    int find_mother();
};
void graph::dfs(int start,bool visited[])
{
    visited[start]=true;
    for(auto itr=adj[start].begin();itr!=adj[start].end();itr++)
    {
        if(!visited[*itr])
        {
            dfs(*itr,visited);
        }
    }
}
int graph::find_mother()
{
    bool *visited=new bool[v];
    for(int i=0;i<v;i++)
        visited[i]=false;
    int m=0;
    for(int i=0;i<v;i++)
    {
        if(visited[i]==false)
        {
            dfs(i,visited);
            m=i;
        }
    }
    for(int i=0;i<v;i++)
        visited[i]=false;
    dfs(m,visited);
    for(int i=0;i<v;i++)
    {
        if(visited[i]==false)
            return -1;
    }
    return m;
}
int main()
{
    graph g(5);
    g.add_edge(0,1);
    g.add_edge(0,2);
    g.add_edge(1,2);
    g.add_edge(2,3);
    g.add_edge(2,0);
    cout<<g.find_mother()<<endl;
    return 0;
}

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