Predict the output of following C programs.
// PROGRAM 1 #include <stdio.h> #include <stdlib.h> int main(void) { static int *p = (int*)malloc(sizeof(p)); *p = 10; printf("%d", *p); } |
// PROGRAM 2 #include <stdio.h> #include <stdlib.h> int *p = (int*)malloc(sizeof(p)); int main(void) { *p = 10; printf("%d", *p); } |
Both of the above programs don’t compile in C. We get the following compiler error in C.
error: initializer element is not constant
In C, static and global variables are initialized by the compiler itself. Therefore, they must be initialized with a constant value.
Note that the above programs compile and run fine in C++, and produce the output as 10.
As an exercise, predict the output of following program in both C and C++.
#include <stdio.h> int fun(int x) { return (x+5); } int y = fun(20); int main() { printf("%d ", y); } |
This article is contributed by Shankar Shastri. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.
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