C Programming MCQ
C is a Procedural Programming Language, mostly written to code an Operating System. C is one of the most famous programming languages and is the forefather of C++, one of the most widely used programming languages today. It has many features some of which are listed below:
- Easy to understand.
- Efficient Memory Usage.
- Usage of Pointers.
- Fast.
- Structured Programming Language.
- Mid-Level Programming Language.
- Portable on all machines.
- Rich user library.
Components of a C Program:
The main components constituting a C program are listed below:
- Header Files: A header file is a file that has an extension .h and contains C function declarations and macros, which are to be shared between several source files, hence allowing reusability and hence more efficiency in building up programming logic.
- Main Method: The main method is a function from where the program execution starts in C.
- Program Body: The program body is the main part of the program where all the programming logic is written. It includes all the variable declarations, the program logic(loops, conditional statements, function calls, etc), and finally the return statement terminating the program.
What will be the result of the following code snippet?
#include <stdio.h>
void solve() {
char ch[10] = "abcdefghij";
int ans = 0;
for(int i = 0; i < 10; i++) {
ans += (ch[i] - 'a');
}
printf("%d", ans);
}
int main() {
solve();
return 0;
}45
36
20
100
What will be the output of the following code snippet?
#include <stdio.h>
struct School {
int age, rollNo;
};
void solve() {
struct School sc;
sc.age = 19;
sc.rollNo = 82;
printf("%d %d", sc.age, sc.rollNo);
}
int main() {
solve();
return 0;
}19 82
Compilation Error
82 19
None of the above.
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
int a[] = {1, 2, 3, 4, 5};
int sum = 0;
for(int i = 0; i < 5; i++) {
if(i % 2 == 0) {
sum += *(a + i);
}
else {
sum -= *(a + i);
}
}
printf("%d", sum);
}
int main() {
solve();
return 0;
}2
15
Syntax Error
3
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
int x = 2;
printf("%d", (x << 1) + (x >> 1));
}
int main() {
solve();
return 0;
}5
4
2
1
What will be the output of the following code snippet?
#include <stdio.h>
#define VAL 5
int getInput() {
return VAL;
}
void solve() {
const int x = getInput();
printf("%d", x);
}
int main() {
solve();
return 0;
}5
Garbage Value
Compilation Error
0
What will be the output of the following code snippet?
#include <stdio.h>
#define CUBE(x) x * x * x
void solve() {
int ans = 216 / CUBE(3);
printf("%d", ans);
}
int main() {
solve();
return 0;
}8
648
72
None of the above.
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
int n = 24;
int l = 0, r = 100, ans = n;
while(l <= r) {
int mid = (l + r) / 2;
if(mid * mid <= n) {
ans = mid;
l = mid + 1;
}
else {
r = mid - 1;
}
}
printf("%d", ans);
}
int main() {
solve();
return 0;
}5
4
3
6
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
int x = 1, y = 2;
printf(x > y ? "Greater" : x == y ? "Equal" : "Lesser");
}
int main() {
solve();
return 0;
}Greater
Lesser
Equal
None of the above.
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
printf("%d ", 9 / 2);
printf("%f", 9.0 / 2);
}
int main() {
solve();
return 0;
}4 4.5000
4 4.000
4.5000 4.5000
4 4
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
int first = 10, second = 20;
int third = first + second;
{
int third = second - first;
printf("%d ", third);
}
printf("%d", third);
}
int main() {
solve();
return 0;
}10 30
30 10
10 20
20 10
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
bool ok = false;
printf(ok ? "YES" : "NO");
}
int main() {
solve();
return 0;
}Yes
No
Compilation Error
None of the above
What will be the output of the following code snippet?
#include <stdio.h>
#define VAL 3 * (2 + 6)
void solve() {
int a = 10 + VAL;
printf("%d", a);
}
int main() {
solve();
return 0;
}104
24
10
34
What will be the output of the following code snippet?
#include <stdio.h>
int main() {
int a = 3, b = 5;
int t = a;
a = b;
b = t;
printf("%d %d", a, b);
return 0;
}3 5
3 3
5 5
5 3
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
int ch = 2;
switch(ch) {
case 1: printf("1 ");
case 2: printf("2 ");
case 3: printf("3 ");
default: printf("None");
}
}
int main() {
solve();
return 0;
}1 2 3 None
2
2 3 None
None
What will be the value of x in the following code snippet?
#include <stdio.h>
void solve() {
int x = printf("Hello");
printf(" %d", x);
}
int main() {
solve();
return 0;
}10
5
1
0
Which data structure is used to handle recursion in C?
Stack.
Queue.
Deque.
Trees.
Which of the following are correct file opening modes in C?
r
rb
w
All of the above.
Which of the following are not standard header files in C?
stdio.h
stdlib.h
conio.h
None of the above.
Which of the following function is used to open a file in C++?
fopen
fclose
fseek
fgets
Which of the following is an exit controlled loop?
While loop.
For loop.
do-while loop.
None of the above.
Which of the following is not a storage class specifier in C?
volatile
extern
typedef
static
Which of the following is not true about structs in C?
No Data Hiding.
Functions are allowed inside structs.
Constructors are not allowed inside structs.
Cannot have static members in the struct body.
Which of the following is the proper syntax for declaring macros in C?
#define long long ll
#define ll long long
#define ll
#define long long
Which of the following should be used to free memory from a pointer allocated using the “new” operator?
free()
delete
realloc()
None of the above.
Which of the following will occur if we call the free() function on a NULL pointer?
Compilation Error.
Runtime Error.
Undefined Behaviour.
The program will execute normally.
What is the output of the following code snippet?
int main() {
int sum = 2 + 4 / 2 + 6 * 2;
printf("%d", sum);
return 0;
}2
15
16
18
What will be the output of the following code snippet?
#include <stdio.h>
union School {
int age, rollNo;
double marks;
};
void solve() {
union School sc;
sc.age = 19;
sc.rollNo = 82;
sc.marks = 19.04;
printf("%d", (int)sizeof(sc));
}
int main() {
solve();
return 0;
}4
8
16
12
How are String represented in memory in C?
An array of characters.
The object of some class.
Same as other primitive data types.
LinkedList of characters.
How is an array initialized in C language?
int a[3] = {1, 2, 3};
int a = {1, 2, 3};
int a[] = new int[3]
int a(3) = [1, 2, 3];
How is the 3rd element in an array accessed based on pointer notation?
*a + 3
*(a + 3)
*(*a + 3)
&(a + 3)
How to declare a double-pointer in C?
int *val
int **val
int &val
int *&val
How to find the length of an array in C?
sizeof(a)
sizeof(a[0])
sizeof(a) / sizeof(a[0])
sizeof(a) * sizeof(a[0])
If p is an integer pointer with a value 1000, then what will the value of p + 5 be?
1020
1005
1004
1010
In which of the following languages is function overloading not possible?
C
C++
Java
Python
What does the following declaration indicate?
int x: 8;
x stores a value of 8.
x is an 8-bit integer.
Both A and B.
None of the above.
What is the disadvantage of arrays in C?
The amount of memory to be allocated should be known beforehand.
Elements of an array can be accessed in constant time.
Elements are stored in contiguous memory blocks.
Multiple other data structures can be implemented using arrays.
What is the output of the following code snippet?
#include <stdio.h>
int main() {
int a[] = {1, 2, 3, 4};
int sum = 0;
for(int i = 0; i < 4; i++) {
sum += a[i];
}
printf("%d", sum);
return 0;
}1
4
20
10
What is the output of the following code snippet?
#include <stdio.h>
#include<stdlib.h>
void set(int *to) {
to = (int*)malloc(5 * sizeof(int));
}
void solve() {
int *ptr;
set(ptr);
*ptr = 10;
printf("%d", *ptr);
}
int main() {
solve();
return 0;
}10
Garbage Value
Cannot Say
The program may crash.
What is the range of values that can be stored by int datatype in C?
-(2^31) to (2^31) - 1
-256 to 255
-(2^63) to (2^63) - 1
0 to (2^31) - 1
What is the return type of the fopen() function in C?
Pointer to a FILE object.
Pointer to an integer.
An integer.
An integer.
What is the size of the int data type (in bytes) in C?
4
8
2
1
What will be the output of the following code snippet?
#include <stdio.h>
int get(int n) {
if(n <= 1) {
return n;
}
return get(n - 1) + get(n - 2);
}
void solve() {
int ans = get(6);
printf("%d", ans);
}
int main() {
solve();
return 0;
}5
1
0
8
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
printf("%d %d", (023), (23));
}
int main() {
solve();
return 0;
}023 23
23 23
19 23
23 19
What will be the output of the following code snippet?
#include <stdio.h>
struct School {
int age, rollNo;
};
void solve() {
struct School sc;
sc.age = 19;
sc.rollNo = 82;
printf("%d", (int)sizeof(sc));
}
int main() {
solve();
return 0;
}1
4
8
16
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
int a = 3;
int res = a++ + ++a + a++ + ++a;
printf("%d", res);
}
int main() {
solve();
return 0;
}12
24
20
18
What will be the output of the following code snippet?
#include <stdio.h>
void solve() {
printf("%d %d %d", (076), (28), (0x87));
}
int main() {
solve();
return 0;
}76 28 87
076 28 0x87
62 28 135
0 0 0
What will be the output of the following code snippet?
#include <stdio.h>
#include<string.h>
void solve() {
char s[] = "Hello";
printf("%s ", s);
char t[40];
strcpy(t, s);
printf("%s", t);
}
int main() {
solve();
return 0;
}Hello Hello
Hello
Compilation Error
None of the above.
What will be the output of the following code snippet?
#include <stdio.h>
void solve(int x) {
if(x == 0) {
printf("%d ", x);
return;
}
printf("%d ", x);
solve(x - 1);
printf("%d ", x);
}
int main() {
solve(3);
return 0;
}3 2 1 0 1 2 3
3 2 1 0
0 1 2 3
None of the above
What will be the output of the following code snippet?
#include <stdio.h>
void swap(int *a, int *b) {
int t = *a;
*a = *b;
*b = t;
}
void solve() {
int a = 3, b = 5;
swap(&a, &b);
printf("%d %d", a, b);
}
int main() {
solve();
return 0;
}3 5
5 3
5 5
3 3
What will be the output of the following code snippet?
#include <stdio.h>
int search(int l, int r, int target, int a[]) {
int mid = (l + r) / 2;
if(a[mid] == target) {
return mid;
}
else if(a[mid] < target) {
return search(mid + 1, r, target, a);
}
else {
return search(0, mid - 1, target, a);
}
}
void solve() {
int a[] = {1, 2, 3, 4, 5};
printf("%d", search(0, 5, 3, a));
}
int main() {
solve();
return 0;
}2
3
4
5
