Create is-graph-bipartite.cpp

Author: kamyu104

Diff for: C++/is-graph-bipartite.cpp

@@ -0,0 +1,28 @@
+// Time:  O(|V| + |E|)
+// Space: O(|V|)
+
+class Solution {
+public:
+    bool isBipartite(vector<vector<int>>& graph) {
+        unordered_map<int, int> color;
+        for (int node = 0; node < graph.size(); ++node) {
+            if (color.count(node)) {
+                continue;
+            }
+            vector<int> stack{node};
+            color[node] = 0;
+            while (!stack.empty()) {
+                int curr = stack.back(); stack.pop_back();
+                for (const auto& neighbor : graph[curr]) {
+                    if (!color.count(neighbor)) {
+                        stack.emplace_back(neighbor);
+                        color[neighbor] = color[curr] ^ 1;
+                    } else if (color[neighbor] == color[curr]) {
+                        return false;
+                    }
+                }
+            }
+        }
+        return true;
+    }
+};