Language: C++

#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <cmath>
#include <map>
#include <iomanip>
#include <deque>
typedef long long ll;
#define rep(i,a,b) for(int i=a;i<b;++i)
#define rrep(i,a,b) for(int i=a;i>=b;--i)
using namespace std;
using vi = vector<int>;
using vll = vector<ll>;
ll mod = 1e9 + 7;
ll llmax = 10000000000000000000ll;
using namespace std;
using Graph = vector<vector<int>>;
Graph G;
const int AMAX = 100000;
/*int cnt_digit(ll N)
{
	int digit = 0;

	while (N > 0)
	{
		N /= 10;
		digit++;
	}
	return digit;
}



int n;
vll a;

ll solve(bool isp)
{
	ll sum = 0ll;
	ll ret = 0ll;

	for (int i = 0; i < n; i++)
	{
		sum += a[i];
		if (isp and sum <= 0)
		{
			ret += -sum + 1;
			sum = 1ll;
		}
		if (not isp and sum >= 0)
		{
			ret += sum + 1;
			sum = -1ll;
		}
		isp ^= 1;
	}
	return ret;
}

*/


/*
 * 最大公約数計算
 */
ll gcd(ll a, ll b)
{
	if (b == 0) {
		return a;
	}
	else {
		return gcd(b, a % b);
	}
}

ll lcm(ll a, ll b)
{
	ll g = gcd(a, b);

	return a / g * b;
}

int main()
{
	cin.tie(0);
	ios::sync_with_stdio(false);
	
	int s;
	cin >> s;
	vector <ll> data(s);
	string ans;
	for (int i = 0;i<s;i++)
	{
		cin >> data[i];
	}
	map <int, int> box;
	for (int i = 0; i < s; i++)
	{
		box[data[i] - 1]++;
		box[data[i]]++;
		box[data[i + 1]]++;
	}
	int ans = 0;
	for (auto x : box)
	{
		ans = max(ans, x.second);
	}
	cout << ans << endl;

	return 0;

}


Compiler output:
a.cc:16:12: warning: integer constant is so large that it is unsigned
   16 | ll llmax = 10000000000000000000ll;
      |            ^~~~~~~~~~~~~~~~~~~~~~
a.cc: In function 'int main()':
a.cc:104:13: error: conflicting declaration 'int ans'
  104 |         int ans = 0;
      |             ^~~
a.cc:92:16: note: previous declaration as 'std::string ans'
   92 |         string ans;
      |                ^~~
a.cc:107:26: error: no matching function for call to 'max(std::string&, int&)'
  107 |                 ans = max(ans, x.second);
      |                       ~~~^~~~~~~~~~~~~~~
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:107:26: note:   deduced conflicting types for parameter 'const _Tp' ('std::__cxx11::basic_string<char>' and 'int')
  107 |                 ans = max(ans, x.second);
      |                       ~~~^~~~~~~~~~~~~~~
/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:3:
/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:107:26: note:   'std::__cxx11::basic_string<char>' is not derived from 'std::initializer_list<_Tp>'
  107 |                 ans = max(ans, x.second);
      |                       ~~~^~~~~~~~~~~~~~~