C MCQs - 9

What will be the output of the following code snippet?

#include <stdio.h>
int main() {
    int x = 0;
    while (x < 5) {
        printf("%d ", x++);
    }
    return 0;
}
 

a) 0 1 2 3 4
b) 1 2 3 4 5
c) 0 1 2 3
d) Infinite loop

Answer: a) 0 1 2 3 4

In C, which function is used to read a line from a file?

a) fgets()
b) gets()
c) scanf()
d) read()

Answer: a) fgets()

What will be the output of the following code?

#include <stdio.h>
int main() {
    int x = 10;
    printf("%f\n", (float)x);
    return 0;
}
 

a) 10.000000
b) 10
c) Compiler error
d) Undefined behavior

Answer: a) 10.000000

Which of the following functions is used to find the square root of a number in C?

a) sqrt()
b) pow()
c) sqr()
d) root()

Answer: a) sqrt()

What will be the output of the following code?

#include <stdio.h>
int main() {
    char str[] = "Hello";
    printf("%s\n", str + 2);
    return 0;
}
 

a) Hello
b) lo
c) ello
d) Compiler error

Answer: b) lo

Which operator is used to access the member of a structure in C?

a) . (dot)
b) -> (arrow)
c) : (colon)
d) :: (double colon)

Answer: a) . (dot)

What will be the output of the following code?

#include <stdio.h>
int main() {
    int x = 5, y = 10;
    printf("%d\n", (x > y) ? x : (y > x) ? y : (x = y));
    return 0;
}
 

a) 5
b) 10
c) 15
d) Compiler error

Answer: b) 10

Which of the following is NOT a valid way to declare a structure variable in C?

a) struct { int x; } s;
b) struct s { int x; };
c) struct s { int x; } s;
d) struct s { int x; } s = {5};

Answer: a) struct { int x; } s;

What will be the output of the following code snippet?

#include <stdio.h>
int main() {
    int i = 0;
    while (++i < 5) {
        printf("%d ", i++);
    }
    printf("%d\n", i);
    return 0;
}
 

a) 1 3 5
b) 1 2 3 4
c) 2 4 6
d) 1 2 3

Answer: b) 1 2 3 4

Which function is used to convert a floating-point number to a string in C?

a) atof()
b) ftoa()
c) dtoa()
d) float_to_string()

Answer: c) dtoa()