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Difference between int32_t main() , int main() , signed main()...
By AnkanNayak, history, 22 months 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.

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22 months ago, # |
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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.

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    22 months ago, # ^ |
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    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?

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      22 months ago, # ^ |
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      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.

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22 months ago, # |
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totally agree with lis05

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

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

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