The Rest Of It

1. Which of the following statements are true.

1. We have to declare a label before using it.

Ans: False. Labels are not declared.

 

2. Scope of a label is limited to the function in which it is placed.

Ans: True.

 

3. A label can be placed in the middle of an expression.

Ans: False. Label is placed at the beginning of a statement.

 

4. As a good programming practice we should avoid using goto

Ans: True.

 

5. Use of goto is recommended only for cases where we do not know how control will flow.

Ans: False. Use of goto is not recommended.

 

 

2. Which of the following statements are true.

1. Inline functions are textually substituted in the program.

Ans: False. Inline functions are merely an optimization hint.

 

2. inline is a hint to compiler to optimize execution time of a function.

Ans: True.

 

3. A static variable is initialized before program execution begins.

Ans: True

 

4. A local static variable can be accessed by any function in the file.

Ans: False. It is visible only inside the function. You can however use a pointer to access it.

 

5. An extern variable declaration does not allocate any memory for the variable.

Ans: True.

 

 

3. Which of the following statements are true.

1. In a recursive function, we should check base condition before recursive call.

Ans: True.

 

2. An infinite recursion will eventually evaluate to zero.

Ans: False. It will keep running forever.

 

3. A recursive function cannot be called with pointer arguments.

Ans: False. It can be called with any type of arguments.

 

4. If a function calls itself, it is called direct recursion.

Ans: True.

 

 

4. Implement recursive program for computing n factorial.

#include <stdio.h>

unsigned long int factorial(unsigned long n) {
    if(1 == n) {
        return 1;
    }
    return n * factorial(n-1);
}

int main (int argc, char *argv[]) {
    unsigned int num = 0;
    unsigned long result = 0;

    printf("Enter a positive number: ");
    scanf("%u", &num);

    if(num == 0) {
        result = 1;
    } else {
        result = factorial(num);
    }
    printf("%u! = %lu\n", num, result);
    return 0;
}

 

 

5. Implement recursive program for computing n^th Fibonacci number.

#include <stdio.h>

unsigned long int fibonacci(unsigned long n) {
    if(0 == n) {
        return 0;
    }
    if(1 == n) {
        return 1;
    }
    return (fibonacci(n-1) + fibonacci(n-2));
}

int main (int argc, char *argv[]) {
    unsigned int num = 0;
    unsigned long result = 0;

    printf("Which <u>Fibonacci</u> Number would you like to find: ");
    scanf("%u", &num);

    result = fibonacci(num);
    printf("F(%u) = %lu\n", num, result);
    return 0;
}