Module 9: Structures and Unions - Final Quiz MCQs

What is the size of the following structure on a standard 32/64-bit architecture with 4-byte integer alignment?

#include <stdio.h>

struct Example {
    char a;
    int b;
    char c;
};

int main() {
    printf("%zu", sizeof(struct Example));
    return 0;
}

How much memory is saved by reordering the struct members as shown below?

#include <stdio.h>

struct Optimized {
    int b;
    char a;
    char c;
};

int main() {
    printf("%zu", sizeof(struct Optimized));
    return 0;
}

What is the size of the following union in memory?

#include <stdio.h>

union Packet {
    int id;
    double timestamp;
    char tag[10];
};

int main() {
    printf("%zu", sizeof(union Packet));
    return 0;
}

What is the output of the following union member overwriting on a standard little-endian machine?

#include <stdio.h>

union Value {
    int num;
    char ch;
};

int main() {
    union Value v;
    v.num = 512;
    v.ch = 'A'; // ASCII 65
    printf("%d", v.num);
    return 0;
}

What range of integer values can the priority bit-field hold?

struct Header {
    unsigned int is_active : 1;
    unsigned int priority : 3;
};

What is the output of structure assignment in the following code?

#include <stdio.h>

struct Point { int x, y; };

int main() {
    struct Point p1 = {10, 20};
    struct Point p2 = p1;
    p2.x = 99;
    printf("%d %d", p1.x, p2.x);
    return 0;
}