Language: C++

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=n-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define all(x) (x).begin(),(x).end()
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[8]={1,0,-1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
using Graph = vector<vector<int>>;
const double pi=acos(-1);
template<int MOD> struct Fp {
    long long val;
    constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
        if (val < 0) val += MOD;
    }
    constexpr int getmod() { return MOD; }
    constexpr Fp operator - () const noexcept {
        return val ? MOD - val : 0;
    }
    constexpr Fp operator + (const Fp& r) const noexcept { return Fp(*this) += r; }
    constexpr Fp operator - (const Fp& r) const noexcept { return Fp(*this) -= r; }
    constexpr Fp operator * (const Fp& r) const noexcept { return Fp(*this) *= r; }
    constexpr Fp operator / (const Fp& r) const noexcept { return Fp(*this) /= r; }
    constexpr Fp& operator += (const Fp& r) noexcept {
        val += r.val;
        if (val >= MOD) val -= MOD;
        return *this;
    }
    constexpr Fp& operator -= (const Fp& r) noexcept {
        val -= r.val;
        if (val < 0) val += MOD;
        return *this;
    }
    constexpr Fp& operator *= (const Fp& r) noexcept {
        val = val * r.val % MOD;
        return *this;
    }
    constexpr Fp& operator /= (const Fp& r) noexcept {
        long long a = r.val, b = MOD, u = 1, v = 0;
        while (b) {
            long long t = a / b;
            a -= t * b; swap(a, b);
            u -= t * v; swap(u, v);
        }
        val = val * u % MOD;
        if (val < 0) val += MOD;
        return *this;
    }
    constexpr bool operator == (const Fp& r) const noexcept {
        return this->val == r.val;
    }
    constexpr bool operator != (const Fp& r) const noexcept {
        return this->val != r.val;
    }
    friend constexpr ostream& operator << (ostream &os, const Fp<MOD>& x) noexcept {
        return os << x.val;
    }
    friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
        if (n == 0) return 1;
        auto t = modpow(a, n / 2);
        t = t * t;
        if (n & 1) t = t * a;
        return t;
    }
};
using mint = Fp<MOD>;
vector<bool> seen,finished;
int pos = -1;
int ca=0;
int f=0;
void dfs(const Graph &G, int v, int p) {
    seen[v] = true;
    for (auto nv : G[v]) {
        if (nv == p) continue;
        if (finished[nv]) continue;
      if (seen[nv] && !finished[nv]) {
            pos = nv;f++; 
            return;
        }
      dfs(G, nv, v);

        // サイクル検出したならば真っ直ぐに抜けていく
        if (pos != -1) {
        return;}}
      finished[v] = true;
}
    
mint calc(long long N, long long K) {
    mint res = 1;
    for (long long n = 0; n < K; ++n) {
        res *= (N - n);
        res /= (n + 1);
    }
    return res;
}
int main() {
ll n; cin>>n;
string s; cin>>s;
for(ll i=1; i < (1 << n); i++){
ll a[15]={};
bitset<10> s(i);
string t[5000]={};
ll g = 0;
if(ll k=0; k<n; k++){
if(s.test(k)){
a[k]++;}}
ll m = 0;
s+='a'+ m;
for(ll k=0; k<n; k++){
m+=a[k];
s+='a'+m;}
t[i]=s;
g = i;
}
sort(s,s+g);
rep(i,g){
cout << s[i] << endl;}}

Compiler output:
a.cc: In function 'int main()':
a.cc:116:15: error: expected ')' before ';' token
  116 | if(ll k=0; k<n; k++){
      |   ~           ^
      |               )
a.cc:116:17: error: 'k' was not declared in this scope
  116 | if(ll k=0; k<n; k++){
      |                 ^
a.cc:120:2: error: no match for 'operator+=' (operand types are 'std::bitset<10>' and 'll' {aka 'long long int'})
  120 | s+='a'+ m;
      | ~^~~~~~~~
a.cc:123:2: error: no match for 'operator+=' (operand types are 'std::bitset<10>' and 'll' {aka 'long long int'})
  123 | s+='a'+m;}
      | ~^~~~~~~
a.cc:124:6: error: no match for 'operator=' (operand types are 'std::string' {aka 'std::__cxx11::basic_string<char>'} and 'std::bitset<10>')
  124 | t[i]=s;
      |      ^
In file included from /usr/include/c++/14/string:54,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52,
                 from a.cc:1:
/usr/include/c++/14/bits/basic_string.h:941:8: note: candidate: 'template<class _Tp> std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::_If_sv<_Tp, std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&> std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::operator=(const _Tp&) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]'
  941 |        operator=(const _Tp& __svt)
      |        ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:941:8: note:   template argument deduction/substitution failed:
In file included from /usr/include/c++/14/bits/stl_pair.h:60,
                 from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/type_traits: In substitution of 'template<bool _Cond, class _Tp> using std::enable_if_t = typename std::enable_if::type [with bool _Cond = false; _Tp = std::__cxx11::basic_string<char>&]':
/usr/include/c++/14/bits/basic_string.h:149:8:   required by substitution of 'template<class _CharT, class _Traits, class _Alloc> template<class _Tp, class _Res> using std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::_If_sv = std::enable_if_t<((bool)std::__and_<std::is_convertible<const _Tp&, std::basic_string_view<_CharT, _Traits> >, std::__not_<std::is_convertible<const _Tp*, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>*> >, std::__not_<std::is_convertible<const _Tp&, const _CharT*> > >::value), _Res> [with _Tp = std::bitset<10>; _Res = std::__cxx11::basic_string<char>&; _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]'
  149 |         using _If_sv = enable_if_t<
      |               ^~~~~~
/usr/include/c++/14/bits/basic_string.h:941:8:   required by substitution of 'template<class _Tp> std::__cxx11::basic_string<char>::_If_sv<_Tp, std::__cxx11::basic_string<char>&> std::__cxx11::basic_string<char>::operator=(const _Tp&) [with _Tp = std::bitset<10>]'
  941 |        operator=(const _Tp& __svt)
      |        ^~~~~~~~
a.cc:124:6:   required from here
  124 | t[i]=s;
      |      ^
/usr/include/c++/14/type_traits:2711:11: error: no type named 'type' in 'struct std::enable_if<false, std::__cxx11::basic_string<char>&>'
 2711 |     using enable_if_t = typename enable_if<_Cond, _Tp>::type;
      |           ^~~~~~~~~~~
/usr/include/c++/14/bits/basic_string.h:817:7: note: candidate: 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>& std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::operator=(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]'
  817 |       operator=(const basic_string& __str)
      |       ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:817:37: note:   no known conversion for argument 1 from 'std::bitset<10>' to 'const std::__cxx11::basic_string<char>&'
  817 |       operator=(const basic_string& __str)
      |                 ~~~~~~~~~~~~~~~~~~~~^~~~~
/usr/include/c++/14/bits/basic_string.h:828:7: note: candidate: 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>& std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::operator=(const _CharT*) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]'
  828 |       operator=(const _CharT* __s)
      |       ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:828:31: note:   no known conversion for argument 1 from 'std::bitset<10>' to 'const char*'
  828 |       operator=(const _CharT* __s)
      |                 ~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/basic_string.h:840:7: note: candidate: 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>& std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::operator=(_CharT) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]'
  840 |       operator=(_CharT __c)
      |       ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:840:24: note:   no known conversion for argument 1 from 'std::bitset<10>' to 'char'
  840 |       operator=(_CharT __c)
      |                 ~~~~~~~^~~
/usr/include/c++/14/bits/basic_string.h:858:7: note: candidate: 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>& std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::operator=(std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&&) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]'
  858 |       operator=(basic_string&& __str)
      |       ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:858:32: note:   no known conversion for argument 1 from 'std::bitset<10>' to 'std::__cxx11::basic_string<char>&&'
  858 |       operator=(basic_string&& __str)
      |                 ~~~~~~~~~~~~~~~^~~~~
/usr/include/c++/14/bits/basic_string.h:926:7: note: candidate: 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>& std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::operator=(std::initializer_list<_Tp>) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]'
  926 |       operator=(initializer_list<_CharT> __l)
      |       ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:926:42: note:   no known conversion for argument 1 from 'std::bitset<10>' to 'std::initializer_list<char>'
  926 |       operator=(initializer_list<_CharT> __l)
      |                 ~~~~~~~~~~~~~~~~~~~~~~~~~^~~
a.cc:127:10: error: 'g' was not declared in this scope
  127 | sort(s,s+g);
      |          ^