2023.03.26 Today's Challenge

https://leetcode.com/problems/longest-cycle-in-a-graph/

Longest Cycle in a Graph - LeetCode

가장 긴 사이클 구하는 문제

class Solution:
    def longestCycle(self, edges: List[int]) -> int:
        lcl = -1
        ts = 1
        nvat = [0] * len(edges)

        for n in range(len(edges)):
            if nvat[n] > 0:
                continue
            st = ts
            u = n
            while u != -1 and nvat[u] == 0:
                nvat[u] = ts
                ts += 1
                u = edges[u]
            if u != -1 and nvat[u] >= st:
                lcl = max(lcl, ts-nvat[u])
        
        return lcl