#include <iostream>
#include <bits/stdc++.h>
using namespace std;

int main() {
	// your code goes here
	return 0;
	
	vector<vector<string>> cities = {{"Chennai","Hyderabad"}
,{"Hyderabad","Bangalore"}
,{"Bangalore","Delhi"}
,{"Hyderabad","Delhi"}};

unordered_map <string,vector<string>> adj;
unordered_map <string,int> distance;
unordered_map <string,int> inDegree;
unordered_set <string> citiesSet;
for(auto it :cities )
{
	vector<string> temp;
	if(adj.find(it[0])==adj.end())
	{
		temp.push_back(it[1]);
		adj.insert({it[0],temp});
	}
	else
	{
		temp = adj[it[0]];
		temp.push_back(it[1]);
		adj.insert({it[0],temp});
	}
	
	if(inDegree.find(it[1])==inDegree.end())
	{
		inDegree.insert({it[1],1});
	}
	else
	{
		inDegree[it[1]]++;
	}
	distance[it[0]]=1;
	distance[it[1]]=1;
	
}

}