#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

const int maxN = 55;

int n;
int mat[maxN][maxN];
vector <vector <int>> ans;

void doAns(int x) {
    vector <int> idc, win;
    for (int i = 1; i <= n; i++) {
        if (i == x) {
            continue;
        }
        if (mat[x][i]) {
            win.push_back(i);
        } else {
            idc.push_back(i);
        }
    }
    vector <int> v1, v2;
    for (int a : idc) {
        v1.push_back(a);
    }
    v1.push_back(x);
    for (int b : win) {
        v1.push_back(b);
    }
    reverse(idc.begin(), idc.end());
    reverse(win.begin(), win.end());
    v2.push_back(x);
    for (int b : win) {
        v2.push_back(b);
    }
    for (int a : idc) {
        v2.push_back(a);
    }
    ans.push_back(v1);
    ans.push_back(v2);
}

int main()
{
    //freopen("test.in", "r", stdin);
    int m;
    cin >> n >> m;
    for (int i = 0; i < m; i++) {
        int x, y;
        cin >> x >> y;
        mat[x][y] = 1;
    }
    cout << "YES\n";
    for (int i = 1; i <= n; i++) {
        doAns(i);
    }
    cout << ans.size() << '\n';
    for (auto v : ans) {
        for (int x : v) {
            cout << x << ' ';
        }
        cout << '\n';
    }
    return 0;
}