open /var/local/lib/isolate/443/box/a.out: no such file or directory
main.cpp:1:21: warning: extra tokens at end of #include directive
    1 | #include <iostream> using namespace std; void megold() { int n, x; cin >> n; unsigned long long o = 2 * n; for(int i = 0; i < n; ++i) { cin >> x; o += x; } cout << o; } int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); megold(); }
      |                     ^~~~~
/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/12/../../../x86_64-linux-gnu/crt1.o: in function `_start':
(.text+0x17): undefined reference to `main'
collect2: error: ld returned 1 exit status