LeetCode 886 Possible Bipartition - Walkthrough

let's trace $n = 4$, dislikes = [[1,2],[1,3],[2,4]]. Build graph: $1 \leftrightarrow 2$, $1 \leftrightarrow 3$, $2 \leftrightarrow 4$. Start: color = [-1,-1,-1,-1,-1]. BFS from $1$: color $1$ as $0$. Neighbors of $1$: $2$, $3$. Color both as $1$. Neighbors of $2$: $1$ (color $0$, opposite, good), $4$ (uncolored, color as $0$).

Neighbors of $3$: $1$ (color $0$, opposite, good). Neighbors of $4$: $2$ (color $1$, opposite, good). No conflicts. Return true. Group A: {$1$, $4$}. Group B: {$2$, $3$}.