int a[20];
int length;
length = sizeof(a) / sizeof(int);
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
int a[]= { 1, 2, 3, 4, 5, 6, 7 };
int length = sizeof(a) / sizeof(a[0]); //return 7
#include <stdio.h>#include <stdlib.h>int main(){//a pointer to dynamically allocated memory from the heap is returned. int *a = (int *) malloc(20 * sizeof(int));for(int i = 0; i < 20; i++)a[i] = i + 1;printf("
The contents of the array are:
");for(int i = 0; i < 20; i++)printf("%d ", a[i]);realloc(a, 40);for(int