Altered Structure

Algorithm/DS-Related/Graph/EulerGraph/UVa-10129-PlayOnWords.cpp

@@ -0,0 +1,80 @@
+#include <iostream>
+#include <vector>
+#include <deque>
+#include <string>
+using namespace std;
+struct Graph{
+	int v;
+	int e;
+	vector<vector<int>> adj;
+	vector<bool> visited;
+	
+	Graph(int _v) : v(_v) {
+		adj.resize(v);
+		visited.assign(v, false);
+	}
+	bool validateV(int _v){
+		return ( _v >= 0 && _v < v);
+	}
+	void insert(int _a, int _b){
+		if(!validateV(_a) || !validateV(_b)) return;
+		
+		adj[_a].push_back(_b);
+	}
+	int degree(int _v){
+		if(!validateV(_v)) return 0;
+		return outDegree(_v) + inDegree(_v);
+	}
+	int outDegree(int _v){
+		if(!validateV(_v)) return 0;
+		return adj[_v].size();
+	}
+	int inDegree(int _v){
+		if(!validateV(_v)) return 0;
+		int js = 0;
+		for(auto x : adj){
+			for(int i = 0; i < x.size(); i++){
+				if(x[i] == _v) js++;
+			}
+		}
+		return js;
+	}
+	void dfs(int _v){
+		if(!validateV(_v)) return;
+		if(visited[_v]) return;
+		visited[_v] = true;
+		for(auto x : adj[_v]){
+			dfs(x);
+		}
+	}
+	bool isConnected(){
+		dfs(0);
+		for(auto x : visited){
+			if(!x) return false;
+		}
+		
+		int js = 0;
+		for(int i = 0; i < v; i++){
+			if(degree(i) % 2 == 1) js++;
+		}
+		return (js == 0) || (js == 2);
+	}
+};
+int main(){
+	int n;
+	cin >> n;
+	Graph g(n);
+	vector<string> s;
+	s.resize(n);
+	for(int i = 0; i < n; i++){
+		cin >> s[i];
+	}
+	for(int i = 0; i < n; i++){
+		for(int j = 0; j < n; j++){
+			if(i != j && s[i].back() == s[j].front()) g.insert(i, j);
+		}
+	}
+	g.isConnected() ? cout << "YES" << endl : cout << "NO" << endl;
+	system("pause");
+	return 0;
+}