C Programming - Functions

1. 

Functions cannot return a floating point number

A. Yes
B. No

Answer: Option B

Explanation:

A function can return floating point value.

Example:


#include <stdio.h>
float sub(float, float); /* Function prototype */

int main()
{
    float a = 4.5, b = 3.2, c;
    c = sub(a, b);
    printf("c = %f\n", c);
    return 0;
}
float sub(float a, float b)
{
   return (a - b);
}

Output:
c = 1.300000


2. 

Every function must return a value

A. Yes
B. No

Answer: Option B

Explanation:

No, If a function return type is declared as void it cannot return any value.


3. 

If a function contains two return statements successively, the compiler will generate warnings. Yes/No ?

A. Yes
B. No

Answer: Option A

Explanation:

Yes. If a function contains two return statements successively, the compiler will generate "Unreachable code" warnings.

Example:


#include<stdio.h>
int mul(int, int); /* Function prototype */

int main()
{
    int a = 4, b = 3, c;
    c = mul(a, b);
    printf("c = %d\n", c);
    return 0;
}
int mul(int a, int b)
{
   return (a * b);
   return (a - b); /* Warning: Unreachable code */
}

Output:
c = 12


4. 

Maximum number of arguments that a function can take is 12

A. Yes
B. No

Answer: Option B

Explanation:

No, C can accept upto 127 maximum number of arguments in a function.


5. 

Will the following functions work?

int f1(int a, int b)
{
    return ( f2(20) );
}
int f2(int a)
{
    return (a*a);
}

A. Yes
B. No

Answer: Option A

Explanation:

Yes, It will return the value 20*20 = 400

Example:


#include <stdio.h>
int f1(int, int); /* Function prototype */
int f2(int); /* Function prototype */

int main()
{
    int a = 2, b = 3, c;
    c = f1(a, b);
    printf("c = %d\n", c);
    return 0;
}

int f1(int a, int b)
{
    return ( f2(20) );
}

int f2(int a)
{
    return (a * a);
}

Output:
c = 400