797. All Paths From Source to Target-蒲公英云

797. All Paths From Source to Target

/*
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.

class Solution {
public List column;

public List<List<Integer>> allPathsSourceTarget(int\[\]\[\] graph) \{  
    List<List<Integer>> g = new ArrayList<List<Integer>>();  
    List<Integer> path = new ArrayList<Integer>();  
    path.add(0);  
    DFS(graph,0,g,path);  
    return g;  
\}  
public void DFS(int\[\]\[\] graph, Integer node, List<List<Integer>> g, List<Integer> path)\{  
    if(node==graph.length-1)\{  
        g.add(new ArrayList<Integer>(path));  
        return;  
    \}  
    for(int nextNode:graph\[node\])\{  
        path.add(nextNode);  
        DFS(graph, nextNode, g, path);  
        path.remove(path.size()-1);  
    \}  
\}