Question

What is the correct way of defining the array in c? The following construction doesn’t work,
compiler gives an error “Expected Expression”:

#include <iostream>
#include <unistd.h>

#define Lookup[9][] = {"00", "01", "02", "03", "04", "05", "06", "07", "08"}

Answer 1

The correct way to define and initialize your array is

char Lookup[][3] = {"00", "01", "02", "03", "04", "05", "06", "07", "08"};

Each element of the array Lookup is itself another array of 3 bytes. Counting with the zero terminator, that’s enough space for strings 2 chars long.

The number of elements in the array is available with the expression sizeof Lookup / sizeof *Lookup, as in

int k;
for (k = 0; k < sizeof Lookup / sizeof *Lookup; k++) {
    printf("element at index %d: %s\n", k, Lookup[k]);
}