Language: C++

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
using P = pair<ll, ll>;
using V = vector<ll>;
#define rep(i, n) for(ll i=0;i<(ll)(n);i++)
#define rep1(i, n) for(ll i=1;i<=(ll)(n);i++)
#define rep2(i, m, n) for(ll i=m;i<(ll)(n);i++)
#define rrep(i, n, m) for(ll i=n;i>=(ll)(m);i--)
#define ALL(obj) (obj).begin(), (obj).end()
#define MOD 1000000007
#define INF 1000000000

void solve_abc_d() {
	ll n;
	string s;
	ll ans = 0;

	cin >> n;
	cin >> s;

	V r, g, b;

	rep(i, n) {
		if (s[i] == 'R') {
			r.push_back(i);
		}
		else if (s[i] == 'G') {
			g.push_back(i);
		}
		else if (s[i] == 'B') {
			b.push_back(i);
		}
	}


	// rgb
	rep(i, r.size())rep(j, g.size()) {
		ll ma = max(r[i], g[j]);
		ll mi = min(r[i], g[j]);
		ll d = abs(r[i] - g[j]);

		// out
		ll cnt = 0;
		auto itr = lower_bound(ALL(b), ma + d);
		if (itr != b.end()) {
			if (*itr == ma + d) {
				cnt ++;
			}
		}

		itr = lower_bound(ALL(b), mi - d);
		if (itr != b.end()) {
			if (*itr == mi - d) {
				cnt++;
			}
		}

		// in
		if (d % 2 == 0) {
			itr = lower_bound(ALL(b), ma - d / 2);
			if (itr != b.end()) {
				if (*itr == ma - d / 2) {
					cnt++;
				}
			}
		}

		ans += max(0LL, b.size() - cnt);
	}

	cout << ans << "\n";
}

int main(void) {
	cin.tie(0);
	ios::sync_with_stdio(false);

	solve_abc_d();

	return 0;
}


Compiler output:
a.cc: In function 'void solve_abc_d()':
a.cc:72:27: error: no matching function for call to 'max(long long int, long long unsigned int)'
   72 |                 ans += max(0LL, b.size() - cnt);
      |                        ~~~^~~~~~~~~~~~~~~~~~~~~
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:72:27: note:   deduced conflicting types for parameter 'const _Tp' ('long long int' and 'long long unsigned int')
   72 |                 ans += max(0LL, b.size() - cnt);
      |                        ~~~^~~~~~~~~~~~~~~~~~~~~
/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:72:27: note:   mismatched types 'std::initializer_list<_Tp>' and 'long long int'
   72 |                 ans += max(0LL, b.size() - cnt);
      |                        ~~~^~~~~~~~~~~~~~~~~~~~~