DFS
From Rice Wiki
DFS
Used for cycle detection
Test link to another page: First_Page
Implementation
DFS_visit(u) {
time = time + 1
d[u] = time
color[u] = 'grey'
for each v in adj[u] {
if color[u] == white
DFS_visit(u)
}
f[u] = time++
color[u] = black
}