The word void is a reserved word in C language. You cannot use reserved words as a user-defined variable.
Is this program statement valid? INT = 10.50;
Assuming that INT is a variable of type float, this statement is valid. One may think that INT is a reserved word and must not be used for other purposes. However, recall that reserved words are express in lowercase, so the C compiler will not interpret this as a reserved word.
Write a program to print factorial of given number without using recursion?
#include<stdio.h>
#include<conio.h>
void main(){
int i,fact=1,number;
clrscr();
printf("Enter a number: ");
scanf("%d",&number);
for(i=1;i<=number;i++){
fact=fact*i;
}
printf("Factorial of %d is: %d",number,fact);
getch();
}
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| Asus Most Frequently Asked C Language Interview Questions Answers |
Write a program to print factorial of given number using recursion?
#include<stdio.h>
#include<conio.h>
long factorial(int n) // function to calculate the factorial of a given number.
{
if (n == 0)
return 1;
else
return(n * factorial(n-1)); //calling the function recursively.
}
void main()
{
int number; //declaration of variables.
long fact;
clrscr();
printf("Enter a number: ");
scanf("%d", &number);
fact = factorial(number); //calling a function.
printf("Factorial of %d is %ld\n", number, fact);
getch(); //It reads a character from the keyword.
}
What are actual arguments?
When you create and use functions that need to perform an action on some given values, you need to pass these given values to that function. The values that are being passed into the called function are referred to as actual arguments.
What is a newline escape sequence?
A newline escape sequence is represented by the \n character. This is used to insert a new line when displaying data in the output screen. More spaces can be added by inserting more \n characters. For example, \n\n would insert two spaces. A newline escape sequence can be placed before the actual output expression or after.
What is output redirection?
It is the process of transferring data to an alternative output source other than the display screen. Output redirection allows a program to have its output saved to a file. For example, if you have a program named COMPUTE, typing this on the command line as COMPUTE >DATA can accept input from the user, perform certain computations, then have the output redirected to a file named DATA, instead of showing it on the screen.
What are run-time errors?
These are errors that occur while the program is being executed. One common instance wherein run-time errors can happen is when you are trying to divide a number by zero. When run-time errors occur, program execution will pause, showing which program line caused the error.
What are structure types in C?
Structure types are primarily used to store records. A record is made up of related fields. This makes it easier to organize a group of related data.
What does the characters “r” and “w” mean when writing programs that will make use of files?
“r” means “read” and will open a file as input wherein data is to be retrieved. “w” means “write”, and will open a file for output. Previous data that was stored on that file will be erased.
What is the difference between text files and binary files?
Text files contain data that can easily be understood by humans. It includes letters, numbers and other characters. On the other hand, binary files contain 1s and 0s that only computers can interpret.
is it possible to create your own header files?
Yes, it is possible to create a customized header file. Just include in it the function prototypes that you want to use in your program, and use the #include directive followed by the name of your header file.
What is dynamic data structure?
Dynamic data structure provides a means for storing data more efficiently into memory. Using dynamic memory allocation, your program will access memory spaces as needed. This is in contrast to static data structure, wherein the programmer has to indicate a fix number of memory space to be used in the program.
What are the different data types in C?
The basic data types are int, char, and float. Int is used to declare variables that will be storing integer values. Float is used to store real numbers. Char can store individual character values.
What is the general form of a C program?
A C program begins with the preprocessor directives, in which the programmer would specify which header file and what constants (if any) to be used. This is followed by the main function heading. Within the main function lies the variable declaration and program statement.
What is the difference between functions abs() and fabs()?
These 2 functions basically perform the same action, which is to get the absolute value of the given value. Abs() is used for integer values, while fabs() is used for floating type numbers. Also, the prototype for abs() is under <stdlib.h>, while fabs() is under <math.h>.
What are formal parameters?
In using functions in a C program, formal parameters contain the values that were passed by the calling function. The values are substituted in these formal parameters and used in whatever operations as indicated within the main body of the called function.