C Programming Questions and Answers – Pointer to Structures
C Programming Questions and Answers – Pointer to Structures
1.What is the output of this C code?
#include <stdio.h>
struct p
{
int x;
char y;
};
int main()
{
struct p p1[] = {1, 92, 3, 94, 5, 96};
struct p *ptr1 = p1;
int x = (sizeof(p1) / 3);
if (x == sizeof(int) + sizeof(char))
printf(“%d\n”, ptr1->x);
else
printf(“falsen”);
}
a) Compile time error
b) 1
c) Undefined behaviour
d) false
View Answer
Answer:d
2.What is the output of this C code?
#include <stdio.h>
struct p
{
int x;
char y;
};
int main()
{
struct p p1[] = {1, 92, 3, 94, 5, 96};
struct p *ptr1 = p1;
int x = (sizeof(p1) / sizeof(ptr1));
if (x == 1)
printf(“%d\n”, ptr1->x);
else
printf(“false\n”);
}
a) Compile time error
b) 1
c) false
d) Undefined behaviour
View Answer
Answer:c
3.What is the output of this C code?
#include <stdio.h>
struct p
{
int x;
char y;
};
typedef struct p* q*;
int main()
{
struct p p1[] = {1, 92, 3, 94, 5, 96};
q ptr1 = p1;
printf(“%d\n”, ptr1->x);
}
a) Compile time error
b) 1
c) Undefined behaviour
d) Segmentation fault
View Answer
Answer:a
4.What is the output of this C code?
#include <stdio.h>
struct p
{
int x;
char y;
};
void foo(struct p* );
int main()
{
typedef struct p* q;
struct p p1[] = {1, 92, 3, 94, 5, 96};
foo(p1);
}
void foo(struct p* p1)
{
q ptr1 = p1;
printf(“%d\n”, ptr1->x);
}
a) Compile time error
b) 1
c) Segmentation fault
d) Undefined behaviour
View Answer
Answer:a
5.Which of the following are incorrect syntax for pointer to structure?
(Assuming struct temp{int b;}*my_struct;)
a) *my_struct.b = 10;
b) (*my_struct).b = 10;
c) my_struct->b = 10;
d) Both (a) and (b)
View Answer
Answer:a
6.Which of the following is an incorrect syntax to pass by reference a member of a structure in a function?
(Assume: struct temp{int a;}s;)
a) func(&s.a);
b) func(&(s).a);
c) func(&(s.a));
d) None of the mentioned
View Answer
Answer:d
7.Which of the following structure declaration doesn’t require pass-by-reference?
a) struct{int a;}s;
main(){}
b) struct temp{int a;};
main(){
struct temp s;
}
c) struct temp{int a;};
main(){}
struct temp s;
d) None of the mentioned
View Answer
Answer:d
8.For the following function call which option is not possible?
func(&s.a); //where s is a variable of type struct and a is the member of the struct.
a) Compiler can access entire structure from the function.
b) Individual member’s address can be displayed in structure.
c) Individual member can be passed by reference in a function.
d) Both (b) and (c).
View Answer
Answer:a
9.Comment on the output of this C code?
#include <stdio.h>
struct temp
{
int a;
} s;
void change(struct temp);
main()
{
s.a = 10;
change(s);
printf(“%d\n”, s.a);
}
void change(struct temp s)
{
s.a = 1;
}
a) Output will be 1
b) Output will be 10
c) Output varies with machine
d) Compile time error
View Answer
Answer:b
10.What is the output of this C code?
#include <stdio.h>
struct p
{
int x;
int y;
};
int main()
{
struct p p1[] = {1, 92, 3, 94, 5, 96};
struct p *ptr1 = p1;
int x = (sizeof(p1) / 5);
if (x == 3)
printf(“%d %d\n”, ptr1->x, (ptr1 + x – 1)->x);
else
printf(“false\n”);
}
a) Compile time error
b) 1 5
c) Undefined behaviour
d) false
View Answer
Answer:d
11.What is the output of this C code?
#include <stdio.h>
struct student
{
char *c;
};
void main()
{
struct student m;
struct student *s = &m;
s->c = “hello”;
printf(“%s”, s->c);
}
a) hello
b) Run time error
c) Nothing
d) Depends on compiler
View Answer
Answer:a
12.What is the output of this C code?
#include <stdio.h>
struct student
{
char *c;
};
void main()
{
struct student *s;
s->c = “hello”;
printf(“%s”, s->c);
}
a) hello
b) Segmentation fault
c) Run time error
d) Nothing
View Answer
Answer:b
13.What is the output of this C code?
#include <stdio.h>
struct student
{
char *c;
};
void main()
{
struct student m;
struct student *s = &m;
s->c = “hello”;
printf(“%s”, m.c);
}
a) Run time error
b) Nothing
c) hello
d) Varies
View Answer
Answer:c
14.What is the output of this C code?
#include <stdio.h>
struct student
{
char *c;
};
void main()
{
struct student m;
struct student *s = &m;
(*s).c = “hello”;
printf(“%s”, m.c);
}
a) Run time error
b) Nothing
c) Varies
d) hello
View Answer
Answer:d
15.What is the output of this C code?
#include <stdio.h>
struct student
{
char *c;
};
void main()
{
struct student n;
struct student *s = &n;
(*s).c = “hello”;
printf(“%p\n%p\n”, s, &n);
}
a) Different address
b) Run time error
c) Nothing
d) Same address
View Answer
Answer:d
16.What is the output of this C code?
#include <stdio.h>
struct p
{
int x[2];
};
struct q
{
int *x;
};
int main()
{
struct p p1 = {1, 2};
struct q *ptr1;
ptr1->x = (struct q*)&p1.x;
printf(“%d\n”, ptr1->x[1]);
}
a) Compile time error
b) Segmentation fault/code crash
c) 2
d) 1
View Answer
Answer:b
17.What is the output of this C code?
#include <stdio.h>
struct p
{
int x[2];
};
struct q
{
int *x;
};
int main()
{
struct p p1 = {1, 2};
struct q *ptr1 = (struct q*)&p1;
ptr1->x = (struct q*)&p1.x;
printf(“%d\n”, ptr1->x[0]);
}
a) Compile time error
b) Undefined behaviour
c) Segmentation fault/code crash
d) 1
View Answer
Answer:b
18.What is the output of this C code?
#include <stdio.h>
struct p
{
int x;
int y;
};
int main()
{
struct p p1[] = {1, 2, 3, 4, 5, 6};
struct p *ptr1 = p1;
printf(“%d %d\n”, ptr1->x, (ptr1 + 2)->x);
}
a) 1 5
b) 1 3
c) Compile time error
d) 1 4
View Answer
Answer:a
19.What is the output of this C code?
#include <stdio.h>
struct p
{
int x;
char y;
};
int main(){
struct p p1[] = {1, 92, 3, 94, 5, 96};
struct p *ptr1 = p1;
int x = (sizeof(p1) / sizeof(struct p));
printf(“%d %d\n”, ptr1->x, (ptr1 + x – 1)->x);
}
a) Compile time error
b) Undefined behaviour
c) 1 3
d) 1 5
View Answer
Answer:d
