#include <iostream>
#include <vector>

using namespace std;

struct Edge {
    int fr;
    int to;
};

int main() {
    int n, m;
    cin >> n >> m;
    vector<Edge> edges;
    int left_to_right = 0;
    for (int i = 0; i < m; i++) {
        int fr, to;
        cin >> fr >> to;
        if (fr < to) {
            left_to_right += 1;
        }
        edges.push_back({fr, to});
    }
    cout << "YES\n";
    bool leave_left_to_right = true;
    if ((m - left_to_right) > left_to_right) {
        leave_left_to_right = false;
        cout << (m - left_to_right) << '\n';
    } else {
        cout << left_to_right << '\n';
    }
    for (int i = 0; i < m; i++) {
        if ((edges[i].fr < edges[i].to) == leave_left_to_right) {
            cout << (i + 1) << " ";
        }
    }
    cout << '\n';
}