Data Packet Routing

#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef pair<ll, ll> PLL;
 
const ll INF = 1000000000000000LL;
 
ll n;
 
template<typename T>
void print_vector(vector<T> & v) {
  for (auto x : v) {
    cout << x << " ";
  }
}
 
ll solve() {
  ll n, m;
  cin >> n >> m;
  set<PLL> s;
  ll res = 1;
  for (int i=0; i<m; i++) {
    ll a, b;
    cin >> a >> b;
    auto p = make_pair(a, b);
    if (s.count(p)) {
      res = 2;
    }
    s.insert(p);
  }
 
  return res;
}
 
int main() {
 
  cin.tie(NULL);
  std::ios::sync_with_stdio(false);
 
  ll t;
  cin >> t;
  for (int i=0; i<t; i++) {
    cout << solve() << endl;
  }
  
  return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED