LeetCode 787 Cheapest Flights Within K Stops - Walkthrough

Input: $n=3$, edges $= [(0,1,100), (1,2,100), (0,2,500)]$, $src=0$, $dst=2$, $k=1$. Iteration $1$: prev = [0, Infinity, Infinity]. Relax edges: dist[1] = 100, dist[2] = 500. Iteration $2$: prev = [0, 100, 500]. Relax edges: dist[2] can improve via $0 \to 1 \to 2$ using prev[1] + 100 = 200.

Final dist[2] = 200. This path uses $1$ stop (city $1$), which satisfies $k=1$. The direct flight costs $500$, but the one-stop route costs $200$.