BFS & DFS

.cpp

/*
	Write a BFS program using adjacency list and queue
*/
#include<iostream>
#include<list>
#include<queue>
#include<stack>
using namespace std;
class Graph{
	private:
		int numberOfVertices;
		list<int> *adjList;
	public:
		Graph(int size){
			numberOfVertices = size;
			adjList = new list <int> [size];
		}
		
		void addVertices(int v1, int v2){
			if(v1 <= numberOfVertices && v2 <= numberOfVertices){
				adjList[v1].push_back(v2);
				adjList[v2].push_back(v1);
			}else return;
		}
		
		void show(){
			list<int>:: iterator i;
			for(int j = 0; j < numberOfVertices; j++){
				cout<<j;
				for(i = adjList[j].begin(); i != adjList[j].end(); ++i){
					cout<<" -> "<<*i;
				}
				cout<<endl;
			}
		}
		
		void bfs(){
			queue<int> queue;
			bool isVisited [numberOfVertices] = {false};
//			for(int i = 0; i < numberOfVertices; i++) isVisited[i] = false;
			queue.push(0);
			isVisited[0] = true;
			list<int>:: iterator i;
			cout<<"\nBFS \n";
			while(!queue.empty()){
				int item = queue.front();
				queue.pop();
				for(i = adjList[item].begin(); i != adjList[item].end(); i++){
					if(!isVisited[*i]){
						queue.push(*i);
						isVisited[*i] = true;
					}
				}
				cout<<item<<" ";
			}
		}
		
		void dfs(){
			cout<<"\nDFS ";
			bool isVisited [numberOfVertices];
			for(int i = 0; i < numberOfVertices; i++) isVisited[i] = false;
			dfs(0,isVisited);
		}
		void dfs(int el, bool isVisited []){
			cout<<" "<<el;
			isVisited[el] = true;
			list<int> ::iterator i;
			for(i = adjList[el].begin(); i != adjList[el].end(); i++){
				if(!isVisited[*i]){
					dfs(*i,isVisited);
				}
			}
		}
};
int main(){
	int size; 
	cout<<"\nEnter number of vertices ";
	cin>>size;
	Graph g(size);
	cout<<"\nStart entering edge from one vertex to another eg. 0 -> 2";
	for(int i = 0; i < size; i++){
		cout<<"\nEnter starting vertex ";
		int start;
		cin>>start;
		cout<<"\nEnter ending vertex ";
		int end;
		cin>>end;
		g.addVertices(start,end);
	}
	g.show();
	g.bfs();
	g.dfs();
}