Language: C++

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

//type
#define ll long long
typedef pair<int, int> P;
//定数
#define INF 1000000000000 //10^12:∞
#define MOD 1000000007    //10^9+7:合同式の法
#define MAXR 100000       //10^5:配列の最大のrange
//略記
#define PB push_back //挿入
#define MP make_pair //pairのコンストラクタ
#define F first      //pairの一つ目の要素
#define S second     //pairの二つ目の要素
#define Z class
// OTHER
// xの二乗を返す (関数テンプレート版)
template <typename T>
T square(T x) { return x * x; }
template <class T>
T GCD(T a, T b)
{
    T r;
    while (a)
        r = b, b = a, a = r % a;
    return b;
}
template <class T>
T LCM(T a, T b) { return a / GCD(a, b) * b; }

#define chmax(x, y) (x = max(x, y))
#define chmin(x, y) (x = min(x, y))
// loop
#define rep(i, n) for (int i = 0; i < (n); i++)
#define repd(i, n) for (ll i = n; i >= 0; i--)
#define FOR(i, a, b) for (ll i = a; i <= (b); i++)
#define FORD(i, a, b) for (ll i = a; i >= (b); i--)
#define FORA(i, I) for (const auto &i : I)

// vector
#define ALL(x) x.begin(), x.end()
typedef vector<int> vi;
typedef vector<string> vs;
typedef vector<vi> vvi;
typedef vector<ll> vl;
#define ERASE(x) x.erase(unique(ALL(x)), x.end()); // erase same elements
#define VEC(type, c, n)     \
    std::vector<type> c(n); \
    for (auto &i : c)       \
        std::cin >> i;

// input
#define INIT                          \
    std::ios::sync_with_stdio(false); \
    std::cin.tie(0);
#define VAR(type, ...) \
    type __VA_ARGS__;  \
    MACRO_VAR_Scan(__VA_ARGS__);

// output
template <typename T>
void MACRO_OUT(const T t) { std::cout << t; }

#define OUT(...) MACRO_OUT(__VA_ARGS__);
#define SP std::cout << " ";
#define TAB std::cout << "\t";
#define BR std::cout << "\n";
#define ENDL std::cout << std::endl;

#define YES() printf("YES\n")
#define NO() printf("NO\n")
#define isYES(x) printf("%s\n", (x) ? "YES" : "NO")
#define Yes() printf("Yes\n")
#define No() printf("No\n")
#define yes() printf("yes\n")
#define no() printf("no\n")
#define ln cout << '\n'
template <Z A>
void pr(A a)
{
    cout << a;
    ln;
}
template <Z A, Z B>
void pr(A a, B b)
{
    cout << a << ' ';
}

ll ans = 0;
bool check = 0;
string s, t;
int N = 3;
vector<int> v(N);
int a, b, c, d, n;
int x, y;
int sum;
char ch;

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// cout << (conditon ? (result:  == 1 ): (==0)) << endl; <- output result of if
// long long 型が表せる値の上限はおよそ 9 × 10＾18 です．
int main()
{
    INIT;
    cin >> s;
    cout << s[0] << s.length() - 2 << s[s.length() - 1] << endl;
    return 0;
}


Compiler output:
a.cc:1:2: error: stray '#' in program
    1 | v#include <bits/stdc++.h>
      |  ^
a.cc:1:1: error: 'v' does not name a type
    1 | v#include <bits/stdc++.h>
      | ^
a.cc:6:9: error: 'pair' does not name a type
    6 | typedef pair<int, int> P;
      |         ^~~~
a.cc:43:9: error: 'vector' does not name a type
   43 | typedef vector<int> vi;
      |         ^~~~~~
a.cc:44:9: error: 'vector' does not name a type
   44 | typedef vector<string> vs;
      |         ^~~~~~
a.cc:45:9: error: 'vector' does not name a type
   45 | typedef vector<vi> vvi;
      |         ^~~~~~
a.cc:46:9: error: 'vector' does not name a type
   46 | typedef vector<ll> vl;
      |         ^~~~~~
a.cc: In function 'void MACRO_OUT(T)':
a.cc:63:34: error: 'cout' is not a member of 'std'
   63 | void MACRO_OUT(const T t) { std::cout << t; }
      |                                  ^~~~
a.cc:1:1: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
  +++ |+#include <iostream>
    1 | v#include <bits/stdc++.h>
a.cc: In function 'void pr(A)':
a.cc:82:5: error: 'cout' was not declared in this scope
   82 |     cout << a;
      |     ^~~~
a.cc: In function 'void pr(A, B)':
a.cc:88:5: error: 'cout' was not declared in this scope
   88 |     cout << a << ' ';
      |     ^~~~
a.cc: At global scope:
a.cc:93:1: error: 'string' does not name a type
   93 | string s, t;
      | ^~~~~~
a.cc:95:1: error: 'vector' does not name a type
   95 | vector<int> v(N);
      | ^~~~~~
a.cc: In function 'int main()':
a.cc:55:10: error: 'std::ios' has not been declared
   55 |     std::ios::sync_with_stdio(false); \
      |          ^~~
a.cc:107:5: note: in expansion of macro 'INIT'
  107 |     INIT;
      |     ^~~~
a.cc:56:10: error: 'cin' is not a member of 'std'
   56 |     std::cin.tie(0);
      |          ^~~
a.cc:107:5: note: in expansion of macro 'INIT'
  107 |     INIT;
      |     ^~~~
a.cc:56:10: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
   56 |     std::cin.tie(0);
      |          ^~~
a.cc:107:5: note: in expansion of macro 'INIT'
  107 |     INIT;
      |     ^~~~
a.cc:108:5: error: 'cin' was not declared in this scope
  108 |     cin >> s;
      |     ^~~
a.cc:108:12: error: 's' was not declared in this scope
  108 |     cin >> s;
      |            ^
a.cc:109:5: error: 'cout' was not declared in this scope
  109 |     cout << s[0] << s.length() - 2 << s[s.length() - 1] << endl;
      |     ^~~~
a.cc:109:60: error: 'endl' was not declared in this scope
  109 |     cout << s[0] << s.length() - 2 << s[s.length() - 1] << endl;
      |                                                            ^~~~