Language: C++

#include<iostream>
#include<cstdio>
#include<string>
#include<algorithm>
#include<cstring>
#include<vector>
#include<cmath>
#include<queue>
#include<stack>
using namespace std;
#define INT(x) int x; scanf("%d",&x)
#define LL(x) ll x; scanf("%lld",&x)
#define INPUT(x) cin >> x
#define REP1(x,n) for(int x = 0; x < n; x++)
#define REP2(x,s,e) for(int x = s; x <= e; x++)
#define RREP1(x,n) for(int x = n-1; x >= 0; x--)
#define RREP2(x,s,e) for(int x = s; x >= e; x--)
#define BR printf("\n")
#define INF_INT 2147483647
#define INF_LL 9223372036854775807

typedef long long ll;

int main(){
    INT(n);INT(k);
    
    ll N = n;
    ll K = k;
    
    ll counter = 0;
    
    if(K == 0){
        counter = N;
        counter *= counter;
        cout << counter << endl;
        return 0;
    }
    
    REP2(i,1,N){
        ll amari = N%i;//Kを引いた個数だけ保証
        ll syou = N/i;//最低限保証されてる。
        counter += syou*(max(i-K, 0)) + max(amari-(K-1), 0);
    }
    
    cout << counter << endl;
    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:42:29: error: no matching function for call to 'max(ll, int)'
   42 |         counter += syou*(max(i-K, 0)) + max(amari-(K-1), 0);
      |                          ~~~^~~~~~~~
In file included from /usr/include/c++/14/string:51,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 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:42:29: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   42 |         counter += syou*(max(i-K, 0)) + max(amari-(K-1), 0);
      |                          ~~~^~~~~~~~
/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:4:
/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:42:29: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   42 |         counter += syou*(max(i-K, 0)) + max(amari-(K-1), 0);
      |                          ~~~^~~~~~~~
a.cc:42:44: error: no matching function for call to 'max(ll, int)'
   42 |         counter += syou*(max(i-K, 0)) + max(amari-(K-1), 0);
      |                                         ~~~^~~~~~~~~~~~~~~~
/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:42:44: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'int')
   42 |         counter += syou*(max(i-K, 0)) + max(amari-(K-1), 0);
      |                                         ~~~^~~~~~~~~~~~~~~~
/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
/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:42:44: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   42 |         counter += syou*(max(i-K, 0)) + max(amari-(K-1), 0);
      |                                         ~~~^~~~~~~~~~~~~~~~