Language: C++

#include "bits/stdc++.h"
using namespace std;

const ll MAX_V = 100100;

ll V, E;
vector<ll> G[MAX_V];

ll cnt[2], mark[MAX_V];
bool f[2][MAX_V];

void dfs(ll s, ll n) {

	for (ll i = 0; i < G[s].size(); i++) {
		ll u = G[s][i];
		if(f[n][u]) continue;
		f[n][u] = true;
		cnt[n]++;
		mark[u]++;
		dfs(u, n);
	}
}

int main() {
	cin >> V;
	for (ll i = 0; i < V-1; i++) {
		ll a, b; cin >> a >> b;
		a--; b--;
		G[a].push_back(b);
		G[b].push_back(a);
	}

	f[0][0] = f[0][V-1] = true;
	f[1][0] = f[1][V-1] = true;

	dfs(0, 0);
	dfs(V-1, 1);

	ll bw=0;
	for (ll i = 0; i < V; i++) {
		if(mark[i]==2) bw++;
	}
	cnt[0] -= bw/2;
	cnt[1] -= (bw/2)+(bw%2);

	//cout << cnt[0] <<" "<< cnt[1] << endl;

	if(cnt[0] > cnt[1]) cout << "Fennec" << endl;
	else cout << "Snuke" << endl;
}

Compiler output:
a.cc:4:7: error: 'll' does not name a type
    4 | const ll MAX_V = 100100;
      |       ^~
a.cc:6:1: error: 'll' does not name a type
    6 | ll V, E;
      | ^~
a.cc:7:8: error: 'll' was not declared in this scope
    7 | vector<ll> G[MAX_V];
      |        ^~
a.cc:7:10: error: template argument 1 is invalid
    7 | vector<ll> G[MAX_V];
      |          ^
a.cc:7:10: error: template argument 2 is invalid
a.cc:7:14: error: 'MAX_V' was not declared in this scope
    7 | vector<ll> G[MAX_V];
      |              ^~~~~
a.cc:9:1: error: 'll' does not name a type
    9 | ll cnt[2], mark[MAX_V];
      | ^~
a.cc:10:11: error: 'MAX_V' was not declared in this scope
   10 | bool f[2][MAX_V];
      |           ^~~~~
a.cc:12:6: error: variable or field 'dfs' declared void
   12 | void dfs(ll s, ll n) {
      |      ^~~
a.cc:12:10: error: 'll' was not declared in this scope
   12 | void dfs(ll s, ll n) {
      |          ^~
a.cc:12:16: error: 'll' was not declared in this scope
   12 | void dfs(ll s, ll n) {
      |                ^~
a.cc: In function 'int main()':
a.cc:25:16: error: 'V' was not declared in this scope
   25 |         cin >> V;
      |                ^
a.cc:26:14: error: 'll' was not declared in this scope
   26 |         for (ll i = 0; i < V-1; i++) {
      |              ^~
a.cc:26:24: error: 'i' was not declared in this scope
   26 |         for (ll i = 0; i < V-1; i++) {
      |                        ^
a.cc:27:19: error: expected ';' before 'a'
   27 |                 ll a, b; cin >> a >> b;
      |                   ^~
      |                   ;
a.cc:27:33: error: 'a' was not declared in this scope
   27 |                 ll a, b; cin >> a >> b;
      |                                 ^
a.cc:27:38: error: 'b' was not declared in this scope
   27 |                 ll a, b; cin >> a >> b;
      |                                      ^
a.cc:29:17: error: 'G' was not declared in this scope
   29 |                 G[a].push_back(b);
      |                 ^
a.cc:33:9: error: 'f' was not declared in this scope
   33 |         f[0][0] = f[0][V-1] = true;
      |         ^
a.cc:36:9: error: 'dfs' was not declared in this scope; did you mean 'ffs'?
   36 |         dfs(0, 0);
      |         ^~~
      |         ffs
a.cc:39:9: error: 'll' was not declared in this scope
   39 |         ll bw=0;
      |         ^~
a.cc:40:16: error: expected ';' before 'i'
   40 |         for (ll i = 0; i < V; i++) {
      |                ^~
      |                ;
a.cc:40:24: error: 'i' was not declared in this scope
   40 |         for (ll i = 0; i < V; i++) {
      |                        ^
a.cc:41:20: error: 'mark' was not declared in this scope
   41 |                 if(mark[i]==2) bw++;
      |                    ^~~~
a.cc:41:32: error: 'bw' was not declared in this scope
   41 |                 if(mark[i]==2) bw++;
      |                                ^~
a.cc:43:9: error: 'cnt' was not declared in this scope; did you mean 'int'?
   43 |         cnt[0] -= bw/2;
      |         ^~~
      |         int
a.cc:43:19: error: 'bw' was not declared in this scope
   43 |         cnt[0] -= bw/2;
      |                   ^~