Commit 015cc5f

committed

solves #429: N-ary Tree Level Order Traversal in java

1 parent 219f754 commit 015cc5fCopy full SHA for 015cc5f

File tree

+96

-0

lines changed

+96

-0

lines changed

Lines changed: 1 addition & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -314,6 +314,7 @@`
`314`	`314`	`\| 414 \| [Third Maximum Number](https://leetcode.com/problems/third-maximum-number) \| [![Java](assets/java.png)](src/ThirdMaximumNumber.java) [![Python](assets/python.png)](python/fizz_buzz.py) \| \|`
`315`	`315`	`\| 415 \| [Add Strings](https://leetcode.com/problems/add-strings) \| [![Java](assets/java.png)](src/AddString.java) [![Python](assets/python.png)](python/add_strings.py) \| \|`
`316`	`316`	`\| 422 \| 🔒 [Valid Word Square](https://leetcode.com/problems/valid-word-square) \| \| \|`
	`317`	`+\| 429 \| 🔒 [N-ary Tree Level Order Traversal](https://leetcode.com/problems/n-ary-tree-level-order-traversal) \| [![Java](assets/java.png)](src/NAryTreeLevelOrderTraversal.java) \| \|`
`317`	`318`	`\| 430 \| [Flatten a Multilevel Doubly Linked List](https://leetcode.com/problems/flatten-a-multilevel-doubly-linked-list) \| [![Java](assets/java.png)](src/FlattenAMultiLevelDoublyLinkedList.java) \| \|`
`318`	`319`	`\| 434 \| [Number of Segments in a String](https://leetcode.com/problems/number-of-segments-in-a-string) \| [![Java](assets/java.png)](src/NumberOfSegmentsInString.java) [![Python](assets/python.png)](python/number_of_segments_in_a_string.py) \| \|`
`319`	`320`	`\| 441 \| [Arranging Coins](https://leetcode.com/problems/arranging-coins) \| [![Java](assets/java.png)](src/ArrangingCoins.java) [![Python](assets/python.png)](python/arranging_coins.py) \| \|`

Lines changed: 56 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,56 @@`
	`1`	`+// https://leetcode.com/problems/n-ary-tree-level-order-traversal`
	`2`	`+// T: O(N)`
	`3`	`+// S: O(N)`
	`4`	`+`
	`5`	`+import java.util.ArrayList;`
	`6`	`+import java.util.LinkedList;`
	`7`	`+import java.util.List;`
	`8`	`+import java.util.Queue;`
	`9`	`+`
	`10`	`+public class NAryTreeLevelOrderTraversal {`
	`11`	`+ public static class Node {`
	`12`	`+ public int val;`
	`13`	`+ public List<Node> children;`
	`14`	`+`
	`15`	`+ public Node() {}`
	`16`	`+`
	`17`	`+ public Node(int _val) {`
	`18`	`+ val = _val;`
	`19`	`+ }`
	`20`	`+`
	`21`	`+ public Node(int _val, List<Node> _children) {`
	`22`	`+ val = _val;`
	`23`	`+ children = _children;`
	`24`	`+ }`
	`25`	`+ }`
	`26`	`+`
	`27`	`+ public List<List<Integer>> levelOrder(Node root) {`
	`28`	`+ if (root == null) {`
	`29`	`+ return new ArrayList<>();`
	`30`	`+ }`
	`31`	`+`
	`32`	`+ final List<List<Integer>> result = new ArrayList<>();`
	`33`	`+ final Queue<Node> queue = new LinkedList<>();`
	`34`	`+ List<Integer> current = new ArrayList<>();`
	`35`	`+`
	`36`	`+ queue.add(root);`
	`37`	`+ queue.add(null);`
	`38`	`+`
	`39`	`+ while (!queue.isEmpty()) {`
	`40`	`+ final Node node = queue.poll();`
	`41`	`+ if (node == null) {`
	`42`	`+ result.add(current);`
	`43`	`+ current = new ArrayList<>();`
	`44`	`+ if (!queue.isEmpty()) {`
	`45`	`+ queue.add(null);`
	`46`	`+ }`
	`47`	`+ continue;`
	`48`	`+ }`
	`49`	`+`
	`50`	`+ current.add(node.val);`
	`51`	`+ queue.addAll(node.children);`
	`52`	`+ }`
	`53`	`+`
	`54`	`+ return result;`
	`55`	`+ }`
	`56`	`+}`

Lines changed: 39 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,39 @@`
	`1`	`+// https://leetcode.com/problems/paths-in-matrix-whose-sum-is-divisible-by-k`
	`2`	`+// T: O()`
	`3`	`+// S: O()`
	`4`	`+`
	`5`	`+import java.util.LinkedList;`
	`6`	`+import java.util.Queue;`
	`7`	`+`
	`8`	`+public class PathsInMatrixWhoseSumIsDivisibleByK {`
	`9`	`+ private static final int MODULO = (int) (10e9 + 7);`
	`10`	`+`
	`11`	`+ public int numberOfPaths(int[][] grid, int k) {`
	`12`	`+ final int rows = grid.length, columns = grid[0].length;`
	`13`	`+ // row, column, currentSum`
	`14`	`+ final Queue<int[]> queue = new LinkedList<>();`
	`15`	`+ queue.add(new int[] {0, 0, grid[0][0]});`
	`16`	`+`
	`17`	`+ int paths = 0;`
	`18`	`+`
	`19`	`+ while (!queue.isEmpty()) {`
	`20`	`+ final int[] position = queue.poll();`
	`21`	`+ final int row = position[0], column = position[1], currentSum = position[2];`
	`22`	`+ if (row == rows - 1 && column == columns - 1) {`
	`23`	`+ if (currentSum % k == 0) {`
	`24`	`+ paths = (paths + 1) % MODULO;`
	`25`	`+ }`
	`26`	`+ continue;`
	`27`	`+ }`
	`28`	`+`
	`29`	`+ if (column + 1 < columns) {`
	`30`	`+ queue.add(new int[] { row, column + 1, currentSum + grid[row][column + 1]});`
	`31`	`+ }`
	`32`	`+ if (row + 1 < rows) {`
	`33`	`+ queue.add(new int[] { row + 1, column, currentSum + grid[row + 1][column]});`
	`34`	`+ }`
	`35`	`+ }`
	`36`	`+`
	`37`	`+ return paths;`
	`38`	`+ }`
	`39`	`+}`

Comments

(0)