Language: C++

#include<bits/stdc++.h>
#define INF 1e9
#define llINF 1e18
#define MOD 1000000007
#define pb push_back
#define mp make_pair 
#define F first
#define S second
#define ll long long
#define vi vector<ll>
#define vvi vector<vi>
#define BITLE(n) (1LL<<((ll)n))
#define SUBS(s,f,t) ((s).substr((f),(t)-(f)))
#define ALL(a) (a).begin(),(a).end()
#define Max(a) (*max_element(ALL(a)))
#define Min(a) (*min_element(ALL(a)))
using namespace std;
struct UF
{
  vector<int> par;
  vector<int> sz;
  vector<int> rank;
  UF(int n):par(n),sz(n),rank(n){
    for(int i = 0; i < n; i++){
      par[i] = i;sz[i] = 1;rank[i] = 0;
    }
  }
  int find(int x) {
    if (par[x] == x) return x;
    else return par[x] = find(par[x]);
  }
  void merge(int x, int y) {
    x = find(x); y = find(y);
    if (x == y) return;
    if(rank[x] < rank[y]){
      par[x] = y;
      sz[y] += sz[x];
    }
    else{
      par[y] = x;
      sz[x] += sz[y];
      if(rank[x] == rank[y])rank[x]++;
    }
  }
  bool same(int x, int y) { return find(x) == find(y); }
  int size(int n){return sz[find(n)];}
};

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  ll n,m;cin>>n>>m;
  UF uni(n);
  for(int i=0;i<m;i++){
    ll a,b;cin>>a>>b;
    a--;b--;
    uni.merge(a,b);
  }
  ll ans = 0;
  for(int i=0;i<n;i++){
    ans = max(ans,uni.size(i));
  }
  cout<<ans<<endl;
  return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:61:14: error: no matching function for call to 'max(long long int&, int)'
   61 |     ans = max(ans,uni.size(i));
      |           ~~~^~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   template argument deduction/substitution failed:
a.cc:61:14: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   61 |     ans = max(ans,uni.size(i));
      |           ~~~^~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 2 provided
In file included from /usr/include/c++/14/algorithm:61:
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   template argument deduction/substitution failed:
a.cc:61:14: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   61 |     ans = max(ans,uni.size(i));
      |           ~~~^~~~~~~~~~~~~~~~~