Language: C++

#include <vector>
#include <iostream>
#include <cmath>
#include <map>
#include <algorithm>
#include <fstream>
#include <unistd.h>
#include <string>
#include <numeric>
#include <queue>
#include <deque>
#include <sstream>
#include <iomanip>
using namespace std;
typedef int64_t ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vi> vvi;
typedef vector<vvi> vvvi;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
typedef vector<string> vs;
typedef vector<vector<string>> vvs;
typedef vector<char> vc;
typedef vector<vector<char>> vvc;
typedef pair<int, int> P;
typedef pair<ll, ll> PL;
typedef vector<P> vp;
typedef vector<PL> vpl;
typedef vector<vector<P>> vvp;
typedef vector<vector<PL>> vvpl;
const int INF = 1001001001;
const ll LINF = 1e18;
const double pi = 3.1415926535897932;
const string endstr = "\n";
#define FOR(i, a, b) for(ll i = (a); i < b; i++)
#define REP(i, n) for(ll i = 0; i < n; i++)
#define FORMAP(it, m) for(auto it = m.begin(); it != m.end(); it++)
#define ff first
#define ss second
#define pb push_back

template <typename T>
T gcd(T a, T b) {
    return (a == 0) ? b : gcd(b%a, a);
}
template <typename T>
T lcm(T a, T b) {
    return a / gcd(a, b) * b;
}

bool p_comp_fs(const PL p1, const PL p2){ return p1.first < p2.first;};
bool p_comp_fg(const PL p1, const PL p2){ return p1.first > p2.first;};
bool p_comp_ss(const PL p1, const PL p2){ return p1.second < p2.second;};
bool p_comp_sg(const PL p1, const PL p2){ return p1.second > p2.second;};
template <typename T>
vector<T> uniquen(vector<T> vec){
    vec.erase(unique(vec.begin(), vec.end()), vec.end());
    return vec;
}

struct UnionFind{
    vl par;
    vl rank;
    map<ll, ll> size;
    UnionFind(ll N) : par(N, 0), rank(N, 0){
        for(int i = 0; i < N; i++) par[i] = i;
    }
    
    ll root(ll x){
        if(par[x] == x) return x;
        else{
            par[x] = root(par[x]); // compression
            return par[x];
        }
    }
    
    void unite(ll x, ll y){
        ll rx = root(x); ll ry = root(y);
        if(rx == ry) return;
        if(rank[rx] < rank[ry]) swap(rx, ry);
        if(rank[rx] == rank[ry]) ++rank[rx];
        par[ry] = rx;
        size[rx]++;
    }
    
    ll get_size(ll x){
        return size[root(x)];
    }
    
    bool same(ll x, ll y){
        return root(x) == root(y);
    }
};


int main(){
    ll N, M; cin >> N >> M;
    vl as(M, 0), bs(M, 0);
    REP(i, M){
        ll a, b;
        cin >> a >> b; as[i] = a-1; bs[i] = b-1;
    }
    
    auto uf = UnionFind(N);
    vl ans(M, 0); ans[M-1] = N * (N-1) / 2;
    ll res = ans[M-1]; vb init(M, true);
    for(ll i = M-1; i >= 0; i--){
        ll old_a = uf.get_size(as[i]);
        ll old_b = uf.get_size(bs[i]);
        uf.unite(as[i], bs[i]);
        if(init[as[i]] && init[bs[i]]){
            res -= 1;
        }
        else if(init[as[i]] || init[bs[i]]){
            res -= uf.get_size(as[i]);
        }
        else{
            res -= (old_a + 1) * (old_b + 1);
        }
        init[as[i]] = false; init[bs[i]] = false;
        
        if(i>=1) ans[i-1] = max(res, 0ll);
    }
    REP(i, M) cout << ans[i] << endstr;
    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:124:32: error: no matching function for call to 'max(ll&, long long int)'
  124 |         if(i>=1) ans[i-1] = max(res, 0ll);
      |                             ~~~^~~~~~~~~~
In file included from /usr/include/c++/14/vector:62,
                 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:124:32: note:   deduced conflicting types for parameter 'const _Tp' ('long int' and 'long long int')
  124 |         if(i>=1) ans[i-1] = max(res, 0ll);
      |                             ~~~^~~~~~~~~~
/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,
                 from a.cc:5:
/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:124:32: note:   mismatched types 'std::initializer_list<_Tp>' and 'long int'
  124 |         if(i>=1) ans[i-1] = max(res, 0ll);
      |                             ~~~^~~~~~~~~~