Language: C++

																								v#include <cstdint>
#include <iostream>

namespace null_null {

using i32 = std::int_fast32_t;
using i64 = std::int_fast64_t;
using u32 = std::uint_fast32_t;
using u64 = std::uint_fast64_t;
using usize = std::size_t;

} // namespace null_null

#include <vector>
#include <math.h>

namespace null_null {

void main_() {
  usize N;
  std::cin>>N;
  std::vector<i32>B(N-1);
  for(usize i=0;i<N-1;i++){
    std::cin>>B[i];
  }

  i32 ans=B[0]+B[N-2];
  for(usize i=1;i<N-1;i++){
    ans+=std::min((int)B[i-1],(int)B[i]);
  }

  std::cout<<ans<<std::endl;
}

} // namespace null_null

int main() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);
  null_null::main_();
  return 0;
}

Compiler output:
a.cc:1:194: error: stray '#' in program
    1 |                                                                                                                                                                                                 v#include <cstdint>
      |                                                                                                                                                                                                  ^
a.cc:1:193: error: 'v' does not name a type
    1 |                                                                                                                                                                                                 v#include <cstdint>
      |                                                                                                                                                                                                 ^
In file included from /usr/include/c++/14/iosfwd:42,
                 from /usr/include/c++/14/ios:40,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:2:
/usr/include/c++/14/bits/postypes.h:68:11: error: 'ptrdiff_t' does not name a type
   68 |   typedef ptrdiff_t     streamsize; // Signed integral type
      |           ^~~~~~~~~
/usr/include/c++/14/bits/postypes.h:41:1: note: 'ptrdiff_t' is defined in header '<cstddef>'; this is probably fixable by adding '#include <cstddef>'
   40 | #include <cwchar> // For mbstate_t
  +++ |+#include <cstddef>
   41 | 
In file included from /usr/include/c++/14/bits/exception_ptr.h:38,
                 from /usr/include/c++/14/exception:166,
                 from /usr/include/c++/14/ios:41:
/usr/include/c++/14/new:131:26: error: declaration of 'operator new' as non-function
  131 | _GLIBCXX_NODISCARD void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc)
      |                          ^~~~~~~~
/usr/include/c++/14/new:131:44: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  131 | _GLIBCXX_NODISCARD void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc)
      |                                            ^~~~~~
In file included from /usr/include/wchar.h:35,
                 from /usr/include/c++/14/cwchar:44,
                 from /usr/include/c++/14/bits/postypes.h:40:
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/new:132:41: error: attributes after parenthesized initializer ignored [-fpermissive]
  132 |   __attribute__((__externally_visible__));
      |                                         ^
/usr/include/c++/14/new:133:26: error: declaration of 'operator new []' as non-function
  133 | _GLIBCXX_NODISCARD void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc)
      |                          ^~~~~~~~
/usr/include/c++/14/new:133:46: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  133 | _GLIBCXX_NODISCARD void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc)
      |                                              ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/new:134:41: error: attributes after parenthesized initializer ignored [-fpermissive]
  134 |   __attribute__((__externally_visible__));
      |                                         ^
/usr/include/c++/14/new:140:29: error: 'std::size_t' has not been declared
  140 | void operator delete(void*, std::size_t) _GLIBCXX_USE_NOEXCEPT
      |                             ^~~
/usr/include/c++/14/new:142:31: error: 'std::size_t' has not been declared
  142 | void operator delete[](void*, std::size_t) _GLIBCXX_USE_NOEXCEPT
      |                               ^~~
/usr/include/c++/14/new:145:26: error: declaration of 'operator new' as non-function
  145 | _GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
      |                          ^~~~~~~~
/usr/include/c++/14/new:145:44: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  145 | _GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
      |                                            ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/new:145:52: error: expected primary-expression before 'const'
  145 | _GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
      |                                                    ^~~~~
/usr/include/c++/14/new:147:26: error: declaration of 'operator new []' as non-function
  147 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
      |                          ^~~~~~~~
/usr/include/c++/14/new:147:46: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  147 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
      |                                              ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/new:147:54: error: expected primary-expression before 'const'
  147 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
      |                                                      ^~~~~
/usr/include/c++/14/new:154:26: error: declaration of 'operator new' as non-function
  154 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t)
      |                          ^~~~~~~~
/usr/include/c++/14/new:154:44: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  154 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t)
      |                                            ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/new:154:68: error: expected primary-expression before ')' token
  154 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t)
      |                                                                    ^
/usr/include/c++/14/new:155:73: error: attributes after parenthesized initializer ignored [-fpermissive]
  155 |   __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
      |                                                                         ^
/usr/include/c++/14/new:156:26: error: declaration of 'operator new' as non-function
  156 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&)
      |                          ^~~~~~~~
/usr/include/c++/14/new:156:44: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  156 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&)
      |                                            ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/new:156:68: error: expected primary-expression before ',' token
  156 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&)
      |                                                                    ^
/usr/include/c++/14/new:156:70: error: expected primary-expression before 'const'
  156 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&)
      |                                                                      ^~~~~
/usr/include/c++/14/new:162:26: error: declaration of 'operator new []' as non-function
  162 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t)
      |                          ^~~~~~~~
/usr/include/c++/14/new:162:46: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  162 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t)
      |                                              ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/new:162:70: error: expected primary-expression before ')' token
  162 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t)
      |                                                                      ^
/usr/include/c++/14/new:163:73: error: attributes after parenthesized initializer ignored [-fpermissive]
  163 |   __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
      |                                                                         ^
/usr/include/c++/14/new:164:26: error: declaration of 'operator new []' as non-function
  164 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&)
      |                          ^~~~~~~~
/usr/include/c++/14/new:164:46: error: 'size_t' is not a member of 'std'; did you mean 'size_t'?
  164 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&)
      |                                              ^~~~~~
/usr/lib/gcc/x86_64-linux-gnu/14/include/stddef.h:214:23: note: 'size_t' declared here
  214 | typedef __SIZE_TYPE__ size_t;
      |                       ^~~~~~
/usr/include/c++/14/new:164:70: error: expected primary-expression before ',' token
  164 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&)
      |                                                                      ^
/usr/include/c++/14/new:164:72: error: expected primary-expression before 'const'
  164 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, st