#include <iostream>
#include <vector>
#include <math.h>
using namespace std;
vector<int> arr[110];
vector<int> col(110), cont;
bool used[110];
int err = 0;

void paint(int v, int color) {
    used[v] = true;
    col[v] = color;
    for (int i = 0; i < arr[v].size(); ++i) {
             if (col[arr[v][i]] == 1)
                err = -1;
             if (!used[arr[v][i]])
                if (color == 1)
                    paint(arr[v][i], 2);
                else
                    paint(arr[v][i], 1);
    }
    col[v] = 2;
}

void dfs(int v) {
    used[v] = true;
    for (int i = 0; i < arr[v].size(); ++i) {
             if (!used[arr[v][i]])
                    dfs(arr[v][i]);
    }
    cont.push_back(v);

}

int main() {
    int n, cur, cur1, m;
    cin >> n >> m;
    for (int i = 1; i <= m; ++i) {
        cin >> cur >> cur1;
            arr[cur].push_back(cur1);
    }
    for (int i = 1; i <= n; ++i)
        if (!used[i])
            paint(i, 1);
    if (err == -1)
        cout << "No";
    else {
        cout << "Yes" << '\n';
        fill(used, used + 109, 0);
        for (int i = 1; i <= n; ++i)
            if (!used[i])
                dfs(i);
        vector<int>::reverse_iterator it;
        for (it = cont.rbegin(); it != cont.rend(); ++it) {
            cout << *it << " ";
        }
    }
}