Problems
Find Permutation
Find Permutation
There is a length $n$ sequence $A = (a_1, a_2, ..., a_n)$ that is a permutation of $1, 2, ..., n$.
While you do not know $A$, you know that $A_{x_i} < A_{y_i}$ for $m$ pairs of integers $(x_i, y_i)$.
Can $A$ be uniquely determined? If it is possible, find $A$.
\InputFile
The first line contains two numbers $n\:(2 \le n \le 2 \cdot 10^5)$ and $m\:(1 \le m \le 2 \cdot 10^5)$.
Each of the next $m$ lines contains a pair of integers $(x_i, y_i)$, $1 \le x_i, y_i \le n$.
\OutputFile
If $A$ can be uniquely determined, print \textbf{Yes} in the first line. Then, print $a_1, a_2, ..., a_n$ in the second line.
If $A$ cannot be uniquely determined, just print \textbf{No}.
Input example #1
4 4 3 1 3 4 1 4 4 2
Output example #1
Yes 2 4 1 3
Input example #2
4 4 3 4 1 4 1 2 4 2
Output example #2
No