Struct Padding

Code

#include <stdio.h>
#include <stddef.h>  // for offsetof

typedef struct {
    char a;    // 1 byte
    int b;     // usually 4 bytes, aligned at 4
    short c;   // 2 bytes, aligned at 2
} MyStruct;

void print_offsets() {
    printf("Offset of a: %zu\n", offsetof(MyStruct, a));
    printf("Offset of b: %zu\n", offsetof(MyStruct, b));
    printf("Offset of c: %zu\n", offsetof(MyStruct, c));
    printf("Size: %zu\n", sizeof(MyStruct));
}

int main() {
    MyStruct s;
    print_offsets();
    return 0;
}

Solving Approach