Language: C++

// #pragma GCC target("avx2")
#pragma GCC optimize("O3", "unroll-loops")

// #include <bits/extc++.h>
// using namespace __gnu_pbds;

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define double long double
// template <typename T>
// using pbds_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
using pii = pair<int, int>;
template<typename T>
using prior = priority_queue<T, vector<T>, greater<T>>;
template<typename T>
using Prior = priority_queue<T>;

#define X first
#define Y second
#define ALL(x) (x).begin(), (x).end()
#define eb emplace_back
#define pb push_back

#define fastIO() ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define RANDOM() random_device __rd; \
                 mt19937 __gen = mt19937(__rd()); \
                 uniform_int_distribution<int> __dis(1, 1E8); \
                 auto rnd = bind(__dis, __gen)

const int INF = 1E18;
const int mod = 1E9 + 7;

int32_t main() {
    fastIO();
    
    string s;
    cin >> s;
    cout << regex_replace(s, ",", " ") << "\n";
    
    return 0;
}

Compiler output:
a.cc: In function 'int32_t main()':
a.cc:40:26: error: no matching function for call to 'regex_replace(std::string&, const char [2], const char [2])'
   40 |     cout << regex_replace(s, ",", " ") << "\n";
      |             ~~~~~~~~~~~~~^~~~~~~~~~~~~
In file included from /usr/include/c++/14/regex:68,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:181,
                 from a.cc:7:
/usr/include/c++/14/bits/regex.h:2576:5: note: candidate: 'template<class _Out_iter, class _Bi_iter, class _Rx_traits, class _Ch_type, class _St, class _Sa> _Out_iter std::regex_replace(_Out_iter, _Bi_iter, _Bi_iter, const __cxx11::basic_regex<_Ch_type, _Rx_traits>&, const __cxx11::basic_string<_Ch_type, _St, _Sa>&, regex_constants::match_flag_type)'
 2576 |     regex_replace(_Out_iter __out, _Bi_iter __first, _Bi_iter __last,
      |     ^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2576:5: note:   candidate expects 5 arguments, 3 provided
/usr/include/c++/14/bits/regex.h:2602:5: note: candidate: 'template<class _Out_iter, class _Bi_iter, class _Rx_traits, class _Ch_type> _Out_iter std::regex_replace(_Out_iter, _Bi_iter, _Bi_iter, const __cxx11::basic_regex<_Ch_type, _Rx_traits>&, const _Ch_type*, regex_constants::match_flag_type)'
 2602 |     regex_replace(_Out_iter __out, _Bi_iter __first, _Bi_iter __last,
      |     ^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2602:5: note:   candidate expects 5 arguments, 3 provided
/usr/include/c++/14/bits/regex.h:2628:5: note: candidate: 'template<class _Rx_traits, class _Ch_type, class _St, class _Sa, class _Fst, class _Fsa> std::__cxx11::basic_string<_Ch_type, _St, _Sa> std::regex_replace(const __cxx11::basic_string<_Ch_type, _St, _Sa>&, const __cxx11::basic_regex<_Ch_type, _Rx_traits>&, const __cxx11::basic_string<_Ch_type, _Fst, _Fsa>&, regex_constants::match_flag_type)'
 2628 |     regex_replace(const basic_string<_Ch_type, _St, _Sa>& __s,
      |     ^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2628:5: note:   template argument deduction/substitution failed:
a.cc:40:26: note:   mismatched types 'const std::__cxx11::basic_regex<_Ch_type, _Rx_traits>' and 'const char [2]'
   40 |     cout << regex_replace(s, ",", " ") << "\n";
      |             ~~~~~~~~~~~~~^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2654:5: note: candidate: 'template<class _Rx_traits, class _Ch_type, class _St, class _Sa> std::__cxx11::basic_string<_Ch_type, _St, _Sa> std::regex_replace(const __cxx11::basic_string<_Ch_type, _St, _Sa>&, const __cxx11::basic_regex<_Ch_type, _Rx_traits>&, const _Ch_type*, regex_constants::match_flag_type)'
 2654 |     regex_replace(const basic_string<_Ch_type, _St, _Sa>& __s,
      |     ^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2654:5: note:   template argument deduction/substitution failed:
a.cc:40:26: note:   mismatched types 'const std::__cxx11::basic_regex<_Ch_type, _Rx_traits>' and 'const char [2]'
   40 |     cout << regex_replace(s, ",", " ") << "\n";
      |             ~~~~~~~~~~~~~^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2680:5: note: candidate: 'template<class _Rx_traits, class _Ch_type, class _St, class _Sa> std::__cxx11::basic_string<_Ch_type> std::regex_replace(const _Ch_type*, const __cxx11::basic_regex<_Ch_type, _Rx_traits>&, const __cxx11::basic_string<_Ch_type, _St, _Sa>&, regex_constants::match_flag_type)'
 2680 |     regex_replace(const _Ch_type* __s,
      |     ^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2680:5: note:   template argument deduction/substitution failed:
a.cc:40:26: note:   mismatched types 'const _Ch_type*' and 'std::__cxx11::basic_string<char>'
   40 |     cout << regex_replace(s, ",", " ") << "\n";
      |             ~~~~~~~~~~~~~^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2706:5: note: candidate: 'template<class _Rx_traits, class _Ch_type> std::__cxx11::basic_string<_Ch_type> std::regex_replace(const _Ch_type*, const __cxx11::basic_regex<_Ch_type, _Rx_traits>&, const _Ch_type*, regex_constants::match_flag_type)'
 2706 |     regex_replace(const _Ch_type* __s,
      |     ^~~~~~~~~~~~~
/usr/include/c++/14/bits/regex.h:2706:5: note:   template argument deduction/substitution failed:
a.cc:40:26: note:   mismatched types 'const _Ch_type*' and 'std::__cxx11::basic_string<char>'
   40 |     cout << regex_replace(s, ",", " ") << "\n";
      |             ~~~~~~~~~~~~~^~~~~~~~~~~~~