AnkanNayak's blog

Difference between int32_t main() , int main() , signed main()...
By AnkanNayak, history, 2 years ago, In English

Hello guys, Can someone tell me what's the difference between " int32_t main() ,int64_t main(), int main() , signed main() ...." and when to use what and what's the best for all cases ?

I would really appreciate if you guys can help me out.

  • Vote: I like it
  • -12
  • Vote: I do not like it

Comments Comments (7)
| Write comment?
»
2 years ago, # |
  Vote: I like it +16 Vote: I do not like it

The main function must return a signed 32-bit integer. All of int32_t, int and signed are signed 32-bit integer types.

In cp, people often define int to long long. To prevent compilation errors, they define the main function as a int32_t or signed data type.

→ Reply
  • »
    »
    2 years ago, # ^ |
      Vote: I like it -8 Vote: I do not like it

    thanks,got it,btw when I was searching about it on internet saw "int64_t" ,does it gonna also work on online judges like others?

    → Reply
    • »
      »
      »
      2 years ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      It's not going to work because int64_t is a 64-bit integer type, but the main function must return a 32-bit integer.

      → Reply
»
2 years ago, # |
← Rev. 2   Vote: I like it +6 Vote: I do not like it

totally agree with lis05

interesting note: you can even leave "type" space blank! like just main() {.., only matter of preference, choose whatever you want

→ Reply
  • »
    »
    2 years ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Up to my best knowledge, only in C (or probably some old versions of C++ compilers, not available nowadays on online judges like codeforces)

    → Reply