c语言中获取数组的长度

001、一维数组

[root@PC1 test1]# ls
test.c
[root@PC1 test1]# cat test.c
#include <stdio.h>

int main(void)
{
        int v1[5] = {3, 4, 8};

        printf("length of v1 is %d\n", sizeof(v1)/sizeof(v1[0]));

        return 0;
}
[root@PC1 test1]# gcc test.c -o kkk
[root@PC1 test1]# ls
kkk  test.c
[root@PC1 test1]# ./kkk
length of v1 is 5

。

[root@PC1 test1]# ls
test.c
[root@PC1 test1]# cat test.c
#include <stdio.h>

int main(void)
{
        int v1[8];

        printf("length of v1 is %d\n", sizeof(v1)/sizeof(v1[0]));

        return 0;
}
[root@PC1 test1]# gcc test.c -o kkk
[root@PC1 test1]# ls
kkk  test.c
[root@PC1 test1]# ./kkk
length of v1 is 8

 。

02、二维数组

[root@PC1 test1]# ls
test.c
[root@PC1 test1]# cat test.c
#include <stdio.h>

int main(void)
{
        int v1[4][3] = {{4,3,2},{2,4,8},{0, 3, 4},{7,45,3}};

        printf("length of v1 is %d\n", sizeof(v1)/sizeof(v1[0][0]));

        return 0;
}
[root@PC1 test1]# gcc test.c -o kkk
[root@PC1 test1]# ls
kkk  test.c
[root@PC1 test1]# ./kkk
length of v1 is 12

 。