c related doubt here ?

Question

#include <stdio.h>
struct {
int b1: 1;
int b2: 2;
}bits;
int main() {
printf("%ld",sizeof (bits));
return 0;
}
what does this code mean ? and how the output is 4?

Answer 1

Read about bit-field here 👇

https://en.cppreference.com/w/cpp/language/bit_field