A data pipeline has n stages numbered 0 to n - 1. Each edges[i] = [a, b] means records can flow from stage a to stage b. The edges never form a loop. Stage 0 is the input and stage n - 1 is the output.
Write countRoutes(n, edges) that returns how many different routes go from stage 0 to stage n - 1. Two routes are different if their lists of stages differ. If n = 1, the single stage is one route.
Input: n = 4, edges = [[0,1],[0,2],[1,3],[2,3]] Output: 2
The routes are 0 → 1 → 3 and 0 → 2 → 3.
Input: n = 3, edges = [[0,1]] Output: 0
Stage 2 can't be reached at all.
1 <= n <= 600 <= edges.length <= 5002^53.Run tries your code on the examples. Submit runs every test, including hidden edge cases, and solves the problem when they all pass.
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I'm here to help with #445 Count Routes Through a Pipeline. I give hints, never the solution, so you get to solve it yourself. Ask for a hint, select code to ask about it, or press Ask Tuto why on a failing test.
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