i have a structre related doubt ?

Question

this code works fine:-

#include<stdio.h>
typedef struct{
int b;
}abc;

int main()
{
abc A;
A.b = 10;
printf("%d",A.b);
return 0;
}

But not this:-
#include<stdio.h>

struct{
int b;
};

int main()
{
struct A;
A.b = 10;
printf("%d",A.b);
return 0;
}

Why

Answer 1

You didn't declare the structure in the second code correctly

struct struct_A{
int b;
};

int main()
{
struct struct_A A;
A.b = 10;
printf("%d", A.b);
return 0;
}

Answer 2

ROBIN thanks for your help
now i understand the error as well

ONUR yes now those errors are making sense to me

thanks to u both