Language: C++

#include<bits/stdc++.h>

using namespace std;

#define REP(i,x,y) for (int i=x;i<y;i++)

const int8_t INFC=0x3f;
const int16_t INFS=0x3f3f;
const int32_t INF=0x3f3f3f3f;
const int64_t INFL=0x3f3f3f3f3f3f3f3fLL;

const int MAXN=2e5;
struct UF
{
    int par[MAXN],rk[MAXN];
    void merge(int x,int y)
    {
        if (find(x)==find(y)) return ;
        rk[par[x]]+=rk[par[y]];
        par[y]=par[x];
    }
    int find(int x)
    {
        return x==par[x]?x:par[x]=find(par[x]);
    }
    void init(int n)
    {
        for (int i=0;i<n;i++) par[i]=i,rk[i]=1;
    }
}uf;
int a[MAXN],b[MAXN];
int main()
{
    ios::sync_with_stdio(0);
    int n,m;
    cin >> n >> m;
    uf.init(n);
    for (int i=0;i<m;i++)
    {
        cin >>a[i]>>b[i];
        a[i]--,b[i]--;
    }
    int64_t res=n;
    res*=n-1;
    res/=2;
    vector<int64_t> ans;
    ans.clear();
    for (int i=m-1;i>=0;i--)
    {
        ans.push_back(res);
        res-=uf.rk[uf.find(a[i])]*uf.rk[uf.find(b[i])];
        uf.merge(a[i],b[i]);
    }
    reverse(ans.begin(),ans.end());
    for (int i=m-1;i>=0;i--)
    {
        cout << max(0LL,ans[i]) << endl;
    }
    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:57:20: error: no matching function for call to 'max(long long int, __gnu_cxx::__alloc_traits<std::allocator<long int>, long int>::value_type&)'
   57 |         cout << max(0LL,ans[i]) << endl;
      |                 ~~~^~~~~~~~~~~~
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:57:20: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and '__gnu_cxx::__alloc_traits<std::allocator<long int>, long int>::value_type' {aka 'long int'})
   57 |         cout << max(0LL,ans[i]) << endl;
      |                 ~~~^~~~~~~~~~~~
/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:57:20: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   57 |         cout << max(0LL,ans[i]) << endl;
      |                 ~~~^~~~~~~~~~~~