All Paths From Source to Target

Similar Problems:

Given a directed, acyclic graph of N nodes. Find all possible paths from node 0 to node N-1, and return them in any order.

The graph is given as follows: the nodes are 0, 1, …, graph.length – 1. graph[i] is a list of all nodes j for which the edge (i, j) exists.

Example:

Input: [[1,2], [3], [3], []] Output: [[0,1,3],[0,2,3]] Explanation: The graph looks like this: 0--->1 | | v v 2--->3 There are two paths: 0 -> 1 -> 3 and 0 -> 2 -> 3.

Note:

- The number of nodes in the graph will be in the range [2, 15].
- You can print different paths in any order, but you should keep the order of nodes inside one path.

Github: code.dennyzhang.com

Credits To: leetcode.com

Leave me comments, if you have better ways to solve.

## https://code.dennyzhang.com/all-paths-from-source-to-target ## Basic Ideas: dfs ## Complexity: Time O(n!), Space O(n) class Solution: def allPathsSourceTarget(self, graph): """ :type graph: List[List[int]] :rtype: List[List[int]] """ length = len(graph) if length == 0: return [] if length == 1: return [[0]] self.res, self.l = [], [] self.dfs(0, graph) return self.res def dfs(self, node, graph): if node == len(graph) - 1: self.res.append(self.l + [node]) return self.l.append(node) for edge in graph[node]: self.dfs(edge, graph) self.l.pop(-1)