Welcome toVigges Developer Community-Open, Learning,Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
899 views
in Technique[技术] by (71.8m points)

c - Is it possible that a variable declared after the main has file scope?

After running this code:

#include <stdio.h>
int x;
int main(void)
{
    printf("%d
",x);
    return 0;
}
int x=5; 

I expected the output should be 0. Because of the sequence control structure of the program int x; should be executed first and then 0 is printed and finally int x=5; should be executed. But it is giving the output 5.

How is the program accesses 5 for the x in printf?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

The first acts as a forward declaration, and the later acts as the actual definition.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to Vigges Developer Community for programmer and developer-Open, Learning and Share

2.1m questions

2.1m answers

63 comments

56.6k users

...