Add solution #785

Author: JoshCrozier

README.md

@@ -595,6 +595,7 @@
 782|[Transform to Chessboard](./0782-transform-to-chessboard.js)|Hard|
 783|[Minimum Distance Between BST Nodes](./0783-minimum-distance-between-bst-nodes.js)|Easy|
 784|[Letter Case Permutation](./0784-letter-case-permutation.js)|Medium|
+785|[Is Graph Bipartite?](./0785-is-graph-bipartite.js)|Medium|
 790|[Domino and Tromino Tiling](./0790-domino-and-tromino-tiling.js)|Medium|
 791|[Custom Sort String](./0791-custom-sort-string.js)|Medium|
 796|[Rotate String](./0796-rotate-string.js)|Easy|

solutions/0785-is-graph-bipartite.js

@@ -0,0 +1,58 @@
+/**
+ * 785. Is Graph Bipartite?
+ * https://leetcode.com/problems/is-graph-bipartite/
+ * Difficulty: Medium
+ *
+ * There is an undirected graph with n nodes, where each node is numbered between 0 and n - 1.
+ * You are given a 2D array graph, where graph[u] is an array of nodes that node u is adjacent
+ * to. More formally, for each v in graph[u], there is an undirected edge between node u and
+ * node v. The graph has the following properties:
+ * - There are no self-edges (graph[u] does not contain u).
+ * - There are no parallel edges (graph[u] does not contain duplicate values).
+ * - If v is in graph[u], then u is in graph[v] (the graph is undirected).
+ * - The graph may not be connected, meaning there may be two nodes u and v such that there is
+ *   no path between them.
+ *
+ * A graph is bipartite if the nodes can be partitioned into two independent sets A and B such
+ * that every edge in the graph connects a node in set A and a node in set B.
+ *
+ * Return true if and only if it is bipartite.
+ */
+
+/**
+ * @param {number[][]} graph
+ * @return {boolean}
+ */
+var isBipartite = function(graph) {
+  const n = graph.length;
+  const colors = new Array(n).fill(-1);
+
+  for (let i = 0; i < n; i++) {
+    if (colors[i] === -1 && !colorGraph(i, 0, graph, colors)) {
+      return false;
+    }
+  }
+
+  return true;
+};
+
+function colorGraph(start, color, graph, colors) {
+  const queue = [start];
+  colors[start] = color;
+
+  while (queue.length > 0) {
+    const node = queue.shift();
+    const nextColor = 1 - colors[node];
+
+    for (const neighbor of graph[node]) {
+      if (colors[neighbor] === -1) {
+        colors[neighbor] = nextColor;
+        queue.push(neighbor);
+      } else if (colors[neighbor] !== nextColor) {
+        return false;
+      }
+    }
+  }
+
+  return true;
+}