Walk an Array of Records

Tape and glue sit in separate bins, but the desk needs one total. bins[i] picks a record from the array; .units picks the count in that record. For two bins, the valid indexes are 0 and 1.

#include <stdio.h>
struct Bin { const char *item; int units; };
int main(void) {
    struct Bin bins[] = {{"Tape", 2}, {"Glue", 5}};
    int total = 0;
    for (int i = 0; i < 2; i++) total += bins[i].units;
    printf("Units: %d\n", total);
    return 0;
}

Run the loop to get Units: 7. Change Glue from 5 to 6 and check that the total becomes 8. The condition i < 2 keeps the loop inside the array.