我在这里做错了什么?
$ cat size.c
#include<stdio.h>
#include<math.h>
int main() {
printf ("sizeof unsigned int = %d bytes.\n", sizeof(unsigned int));
printf ("sizeof unsigned long long = %d bytes.\n", sizeof(unsigned long long));
printf ("max unsigned int = %d\n", (int)(pow(2, 32) - 1));
printf ("max unsigned long long = %lld\n", (unsigned long long)(pow(2, 64) - 1));
}
$ gcc size.c -o size
$ ./size
sizeof unsigned int = 4 bytes.
sizeof unsigned long long = 8 bytes.
max unsigned int = 2147483647
max unsigned long long = -1
$
我希望最后一行的输出是18446744073709551615
,而不是-1
。
好的,我完全没有意识到我得到的232 - 1的值是错误的,应该是4294967295,而不是2147483647。现在事情更加合理了。
LLONG_MAX
和LLONG_MIN
),请包含头文件<limits.h>
。 - wkl