Unweighted Paths on NetworkX

Given a directed graph with $n$ vertices and $m$ arcs, we wish to know if there is a directed path between two given vertices.

Input

Input starts with $n$ and $m$ . Then follow $m$ pairs $u,v$ , with $u \ne v$ , indicating an arc from $u$ to $v$ . We have that $0 \leq u < n$ and $0 \leq v < n$ and that there are no repeated arcs. Then follows a pair $x$ , $y$ with $0 \leq x < n$ and $0 \leq y < n$ .

Output

Write “yes” or “no” according to whether there is a path from $x$ to $y$ .

Observation

We are authorized to employ the NetworkX library.

Problem information

Author: José Luis Balcázar, based on problem P56483 by Jordi Petit

Generation: 2026-01-25T14:36:17.396Z