#3812

Minimum Edge Toggles on a Tree

expert · 1025 · lc hard +32 · 69.1% accepted · 40 likes · top 77%

Description

Given an undirected tree of n nodes with edges edges[i] = [ai, bi] and binary strings start and target of length n, each operation picks an edge [u, v] and flips both endpoints' colors; return the sorted list of edge indices for a minimum-length sequence of operations that transforms start into target, or [-1] if no solution exists.

Code

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class Solution:
    def minimumFlips(self, n: int, edges: List[List[int]], start: str, target: str) -> List[int]:

class Solution:
    def minimumFlips(self, n: int, edges: List[List[int]], start: str, target: str) -> List[int]: