length.c

#define length(array) ((sizeof(array)) / (sizeof(array[0])))
type yourArray[] = {your, values};
length(yourArray);    // returns length of yourArray
#include <stdlib.h>
#include <stdio.h>

#define length(array) ((sizeof(array)) / (sizeof(array[0])))


int main()
{
    const char *myStrings[] = {"Foo", "Bar", "Hello, World!"};    // 3 elements
    int myNums[] = {0, 1, 5, 7, 11037};    // 5 elements
    char myChars[] = {'a', 'b', 'c', 'd', 'e', 'f', 'g'};    // 7 elements

    printf("Length of myStrings array: %lu\n", length(myStrings));
    printf("Length of myNums array: %lu\n", length(myNums));
    printf("Length of myChars array: %lu\n", length(myChars));

    return 0;

    /* Output:
           Length of myStrings array: 3
           Length of myNums array: 5
           Length of myChars array: 7 
int *myNums = (int *)malloc(3 * sizeof(int));    // Space for 3 integers
printf("Length of myNums: %lu\n", length(myNums));  // Outputs 2 instead of 3
     */
}