how to take length of array in c code example

Example 1: array length c

int prices[5] = { 1, 2, 3, 4, 5 };

int size = sizeof prices / sizeof prices[0];

printf("%u", size); /* 5 */

Example 2: get length of array in c

int a[17];
size_t n = sizeof(a)/sizeof(a[0]);