#960. Topological sort
You get n tasks and m rules `u v` (u must be done before v); there are no cycles. Of all possible orders, print the lexicographically smallest one.
### Input
n m, then m lines.
### Output
One line.
Examples
Input
5 4 3 2 3 4 3 5 4 5
Output
1 3 2 4 5
Input
6 0
Output
1 2 3 4 5 6
💡 You can solve it with Python, JavaScript or blocks. Read the input line by line with input(). Don't print a question (like input("Number: ")). Print exactly what the output asks for, nothing more.