add cpp solution

Author: jinshendan

May-LeetCoding-Challenge/27-Possible-Bipartition/Possible-Bipartition.cpp

@@ -0,0 +1,36 @@
+class Solution {
+public:
+    vector<int> color;
+    vector<vector<int>> G;
+    
+    bool bipartite(int u) {
+	for (int i = 0; i < G[u].size(); i++) {
+		int v = G[u][i];
+		if (color[v] == color[u]) return false;
+		if (!color[v]) {
+			color[v] = 3 - color[u];
+			if (!bipartite(v)) return false;
+		}
+	}
+	return true;
+}
+    
+    bool possibleBipartition(int N, vector<vector<int>>& dislikes) {
+        color.resize(N+1);
+        G.resize(N+1);
+
+        
+        for (int i = 0; i < dislikes.size(); i++) {
+            G[dislikes[i][0]].push_back(dislikes[i][1]);
+            G[dislikes[i][1]].push_back(dislikes[i][0]);
+        }
+        
+        for (int i = 1; i <= N; i++)
+            if (!color[i]){
+                color[i] = 1;
+                if (!bipartite(i)) return false;
+            }
+        return true;
+        
+    }
+};