代码随想录算法训练营第50天|98. 所有可达路径

打卡Day50

1. 图论理论基础
2. 98. 所有可达路径
3. 广度优先搜索理论基础

1. 图论理论基础

文档讲解：代码随想录

度：无向图中有几条边连接该节点，该节点就有几度
在有向图中，每个节点有出度和入度，出度指从该节点出发的边的个数，而入度是指向该节点边的个数

2. 98. 所有可达路径

题目链接：98. 所有可达路径
文档讲解：代码随想录

#邻接矩阵
def dfs(graph,x,n,path,res):#深度优先搜索#终止条件if x == n:res.append(path.copy())return for i in range(1,n+1):if graph[x][i] == 1:path.append(i)dfs(graph,i,n,path,res)path.pop()n,m = map(int,input().split())
graph = [[0] * (n+1) for _ in range(n+1)]
for _ in range(m):s,t = map(int, input().split())graph[s][t] = 1 
res = []
dfs(graph,1,n,[1],res)
if not res:#结果为空print(-1)
else:for path in res:print(' '.join(map(str,path)))

#邻接表
from collections import defaultdict
def dfs(graph,x,n,res,path):#终止条件if x == n:res.append(path.copy())return for i in graph[x]:#找到x指向的节点path.append(i)dfs(graph,i,n,res,path)path.pop()
n,m = map(int,input().split())
graph = defaultdict(list)
for _ in range(m):s,t = map(int,input().split())graph[s].append(t)
res = []
dfs(graph,1,n,res,[1])
if not res:print(-1)
else:for path in res:print(' '.join(map(str,path)))