Getting weired error in ques 10199 of uva online judge.

10199.cpp

#include<bits/stdc++.h>
using namespace std;
#define ll long long int
const int N=104;
vector<int> g[N],lt,in,ap,vis;
int tim=0;
#define eb emplace_back

void dfs(int node,int par=-1){
	vis[node]=1;
	lt[node]=in[node]=tim++;
	int child=0;
	for(auto it:g[node]){
		if(it==par)continue;
		else if(vis[it]==1)
			lt[node]=min(lt[node],lt[it]);
		else{
			dfs(it,node);
			lt[node]=min(lt[node],lt[it]);
			if(lt[it]>=in[node] && par!=-1)
				ap.eb(node);
			child++;			
		}
	}
	if(par==-1 && child>1)ap.eb(node);
}


int calc(int n){
	for(int i=1;i<=n;i++){
		tim=0;
		if(vis[i]==0)
			dfs(i);
	}
return ap.size();
}

int main(){
	ios_base::sync_with_stdio(false);
	// cin.tie(0);	cout.tie(0);
	int n=1;	cin>>n;
	while(1){
		for(auto &it:g)it.clear();
		lt.resize(n,0);	in.resize(n,0);	ap.clear();	vis.resize(n,0);
		map<string,int> lk;
		int i,j,k,m;
		for(i=1;i<=n;i++){
			string s;
			cin>>s;	lk[s]=i;
		}
		cin>>m;
		while(m--){
			string s,ss;
			cin>>s>>ss;
			g[lk[s]].eb(lk[ss]);
			g[lk[ss]].eb(lk[s]);
		}
		// cout<<"part 1 : \n";
		cout<<calc(n)<<"\n";
		cin>>n;
	}

	return 0;
}