Cin directed and non-directed edges

#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;

#define MAX_N 100000


typedef struct { void *g; } nedge_t;
typedef struct { void *g; } dedge_t;

struct Graph {
    vector<int> edges[MAX_N];
    nedge_t n_edge;
    dedge_t d_edge;

    Graph() {
        n_edge.g = this;
        d_edge.g = this;
    }
};

inline istream& operator>>(istream& in, nedge_t& e) {
    int tmp1, tmp2;
    in >> tmp1 >> tmp2;
    ((Graph*) (e.g))->edges[--tmp1].push_back(--tmp2);
    ((Graph*) (e.g))->edges[tmp2].push_back(tmp1);
    return in;
}

inline istream& operator>>(istream& in, dedge_t& e) {
    int tmp1, tmp2;
    in >> tmp1 >> tmp2;
    ((Graph*) (e.g))->edges[--tmp1].push_back(--tmp2);
    return in;
}

int main() {
    freopen("input.txt", "r", stdin);
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n, m;
    cin >> n >> m;

    Graph g;
    for(int i(0); i < m; ++i)
        cin >> g.d_edge;
    return 0;
}