Files
JavaScript/Trees/DepthFirstSearch.js
Ranganathan7 fc06690672 fixes: #1280 and test: added tests for DFS algorithm (#1303)
* fix: fixed error in DepthFirstSearch algorithm and test: added tests for DepthFirstSearch algorithm.

* changed traverseDFS function parameters in DepthFirstSearch.js file
2023-03-02 00:03:24 +05:30

74 lines
1.8 KiB
JavaScript

/*
* Author: Surendra Kumar
* DFS Algorithm implementation in JavaScript
* DFS Algorithm for traversing or searching graph data structures.
*/
// traverses a give tree from specified root's value
function traverseDFS (tree, rootValue) {
const stack = []
const res = []
stack.push(searchDFS(tree, rootValue))
// if root is not present in the tree, returning empty array
if (!stack[0]) return res
while (stack.length) {
const curr = stack.pop()
res.push(curr.value)
if (curr.left) {
stack.push(tree[curr.left])
}
if (curr.right) {
stack.push(tree[curr.right])
}
}
return res.reverse()
}
function searchDFS (tree, value) {
const stack = []
stack.push(tree[0])
while (stack.length !== 0) {
for (let i = 0; i < stack.length; i++) {
const node = stack.pop()
if (node.value === value) {
return node
}
if (node.right) {
stack.push(tree[node.right])
}
if (node.left) {
stack.push(tree[node.left])
}
}
}
return null
}
const tree = [
{ value: 6, left: 1, right: 2 },
{ value: 5, left: 3, right: 4 },
{ value: 7, left: null, right: 5 },
{ value: 3, left: 6, right: null },
{ value: 4, left: null, right: null },
{ value: 9, left: 7, right: 8 },
{ value: 2, left: 9, right: null },
{ value: 8, left: null, right: null },
{ value: 10, left: null, right: null },
{ value: 1, left: null, right: null }
]
searchDFS(tree, 9) // { value: 9, left: 7, right: 8 }
searchDFS(tree, 200) // null
traverseDFS(tree, 6) // [ 1, 2, 3, 4, 5, 8, 10, 9, 7, 6 ]
traverseDFS(tree, 200) // []
// 6
// / \
// 5 7
// / \ \
// 3 4 9
// / / \
// 2 8 10
// /
// 1
export { searchDFS, traverseDFS }