886. Possible Bipartition

Author: amitbansal7

possible-bipartition.cpp

@@ -0,0 +1,42 @@
+// Runtime: 432 ms
+// Memory Usage: 72.5 MB
+class Solution {
+public:
+
+	bool solve(vector<vector<int> > &adj, vector<bool> &vis, vector<int> &group, int src) {
+		bool res = true;
+		int nextGrp = (group[src] + 1) % 2;
+		for (int a : adj[src]) {
+			if (vis[a] && group[a] == group[src]) {
+				return false;
+			}
+			if (!vis[a]) {
+				group[a] = nextGrp;
+				vis[a] = true;
+				if (!solve(adj, vis, group, a)) {
+					return false;
+				}
+			}
+		}
+		return true;
+	}
+
+	bool possibleBipartition(int N, vector<vector<int>>& dislikes) {
+		vector<vector<int> > adj(N + 1);
+		for (auto a : dislikes) {
+			adj[a[0]].push_back(a[1]);
+			adj[a[1]].push_back(a[0]);
+		}
+		vector<bool> vis(N + 1, 0);
+		vector<int> group(N + 1, -1);
+		for (int i = 1; i <= N; i++) {
+			if (!vis[i]) {
+				group[i] = 0;
+				if (!solve(adj, vis, group, i)) {
+					return false;
+				}
+			}
+		}
+		return true;
+	}
+};