Created
June 8, 2020 23:12
-
-
Save trykhov/03ee11e56dd0620b34a5d70151c6b033 to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| // assuming our adjacency matrix is {A: [B, C, D], B:[D, E], ...} | |
| // assuming that our vertices have the following properties: | |
| // 1. (boolean) visited | |
| // ASSUME graph is a DAG | |
| function topSort(adj) { | |
| // get the number of vertices in the DAG | |
| let numV = Object.keys(adj).length; | |
| // initialize resulting array | |
| let res = Array.new(numV).fill(null); | |
| // get the last index of the array | |
| let openIdx = res.length - 1; | |
| // have a dfs helper function | |
| function dfs(vertex) { | |
| // base case | |
| // if the vertex has already been processed, just ignore it | |
| if(v.visited) return; | |
| // get the neighbors | |
| let neighbors = adj[vertex]; | |
| // loop through the neighbors | |
| for(let v of neighbors) { | |
| // do a DFS if the vertex hasn't been visited | |
| if(!v.visited) dfs(v); | |
| } | |
| // mark the vertex as visited | |
| vertex.visited = true; | |
| // add the vertex to the rightmost open spot in the array | |
| res[openIdx] = vertex; | |
| // move the index to the next open spot on the left | |
| openIdx -= 1; | |
| return; | |
| } | |
| // get the vertices | |
| let vertices = Object.keys(adj); | |
| // do a DFS on all the vertices | |
| for(let v of vertices) { | |
| if(!v.visited) dfs(v); | |
| } | |
| // return the resulting array | |
| return res; | |
| } |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment