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C Program To Print Multiplication Table Using Macros

In this video lets see how we can print multiplication table(from 1 to 10) for any positive user input value, using Macros.

Video Tutorial: C Program To Print Multiplication Table Using Macros

[youtube https://www.youtube.com/watch?v=1IaEnPHRalw]

YouTube Link: https://www.youtube.com/watch?v=1IaEnPHRalw [Watch the Video In Full Screen.]

Source Code: C Program To Print Multiplication Table Using Macros

#include<stdio.h>

#define MULTI(num, count) printf("%d x %d = %d\n", num, count, (num*count))

int main()
{
    int num, count = 1;

    printf("Enter a positive number\n");
    scanf("%d", &num);

    printf("\nMultiplication Table for %d is: \n\n", num);

    while(count <= 10)
    {
        MULTI(num, count);
        count++;
    }

    return 0;
}

Output 1:
Enter a positive number
5

Multiplication Table for 5 is:

5 x 1 = 5
5 x 2 = 10
5 x 3 = 15
5 x 4 = 20
5 x 5 = 25
5 x 6 = 30
5 x 7 = 35
5 x 8 = 40
5 x 9 = 45
5 x 10 = 50

Output 2:
Enter a positive number
4

Multiplication Table for 4 is:

4 x 1 = 4
4 x 2 = 8
4 x 3 = 12
4 x 4 = 16
4 x 5 = 20
4 x 6 = 24
4 x 7 = 28
4 x 8 = 32
4 x 9 = 36
4 x 10 = 40

Here we are initializing variable count to 1 and iterating the while loop until count is less than or equal to 10. For each iteration we’re executing macro MULTI(num, count). But before compilation itself preprocessor will have replaced MULTI(num, count) by its macro expansion, which is printf(“%d x %d = %d\n”, num, count, (num*count)).

Note: If you see \ inside macro expansion – it is called as Macro continuation(\) operator. It is used to continue the code in next line, in macro expansion.

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For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

Positive or Negative or Zero Using Macros: C Program

C Program to check whether the user input integer number is positive, negative or zero using Macros and ternary / Conditional operator.

Logic

If user input number is greater than 0, then the number is positive. If user input number is less than 0, then the number is negative. If neither of the above 2 conditions are true, then the number is zero.

Video Tutorial: Positive or Negative or Zero Using Macros: C Program

[youtube https://www.youtube.com/watch?v=RNSLLP0buyk]

YouTube Link: https://www.youtube.com/watch?v=RNSLLP0buyk [Watch the Video In Full Screen.]

Source Code: Positive or Negative or Zero Using Macros: C Program

#include<stdio.h>

#define SIGN(num) ( (num > 0) ? \
                   printf("POSITIVE") : \
                   (num < 0) ? printf("NEGATIVE") : \
                   printf("ZERO"))

int main()
{
    int num;

    printf("Enter a number\n");
    scanf("%d", &num);

    SIGN(num);

    return 0;
}

Output 1:
Enter a number
5
POSITIVE

Output 2:
Enter a number
-2
NEGATIVE

Output 3:
Enter a number
0
ZERO

Here the macro template SIGN(num) will be replaced by its corresponding macro expansion ( (num > 0) printf(“POSITIVE”) : (num < 0) ? printf(“NEGATIVE”) : printf(“ZERO”)) by preprocessor. And if user input number is greater than 0, it’ll print POSITIVE else it’ll print NEGATIVE. If neither of those 2 conditions are true, then it’ll print ZERO.

In our program we’re using Macro Continuation (\) Preprocessor Operator: C Program in macro expansion to break from the line and continue the logic in new/next line.

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

Even or Odd Number using Macros: C Program

Lets write a C program to find if the user input number is odd or even, using Macros.

Logic To Find Even Or ODD

If user input number is perfectly divisible by 2, then it’s Even number orelse it’s Odd number.

Video Tutorial: Even or Odd Number using Macros: C Program

[youtube https://www.youtube.com/watch?v=QtiHjwNZ7zg]

YouTube Link: https://www.youtube.com/watch?v=QtiHjwNZ7zg [Watch the Video In Full Screen.]

Source Code: Even or Odd Number using Macros: C Program

#include<stdio.h>
#define ODD_EVEN(num) ( (num % 2 == 0) ? printf("Even\n") : printf("ODD\n") )

int main()
{
    int num;

    printf("Enter a positive number\n");
    scanf("%d", &num);

    ODD_EVEN(num);

    return 0;
}

Output 1:
Enter a positive number
5
ODD

Output 2:
Enter a positive number
6
Even

In above program the macro template ODD_EVEN(num) will be replaced by it’s macro expansion ( (num % 2 == 0) ? printf(“Even\n”) : printf(“ODD\n”) ) and hence if the user input number is perfectly divisible by 2, then EVEN will be printed else ODD will be printed.

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

C Program To Determine Leap Year or Not using Macros

In this video tutorial lets learn how to determine user input year is a leap year or not, using Macros and nested ternary / conditional operator.

Leap Year Logic

1. If a year is century year(year ending with 00) and is perfectly divisible by 400, then it’s a leap year.

2. If a year is not a century year, and is perfectly divisible by 4, then it’s a leap year.

Video Tutorial: Determine Leap Year or Not using Macros: C Program

[youtube https://www.youtube.com/watch?v=Du7YNk8GGDk]

YouTube Link: https://www.youtube.com/watch?v=Du7YNk8GGDk [Watch the Video In Full Screen.]

Source Code: C Program To Determine Leap Year or Not using Macros

#include<stdio.h>

#define NOT_LEAP(x) printf("%d is not leap year\n", x)
#define LEAP_YEAR(x) printf("%d is leap year\n", x)

#define LEAP(x) ( (x % 100 == 0 && x % 400 == 0) ? LEAP_YEAR(x) : \
                 ( (x % 4 ==0) ? LEAP_YEAR(x) : NOT_LEAP(x)) )

int main()
{
    int year;

    printf("Enter a year\n");
    scanf("%d", &year);

    LEAP(year);

    return 0;
}

Output 1:
Enter a year
2018
2018 is not leap year

Output 2:
Enter a year
2019
2019 is not leap year

Output 3:
Enter a year
2020
2020 is leap year

Output 4:
Enter a year
2023
2023 is not leap year

Output 5:
Enter a year
2024
2024 is leap year

In above program we’re writing NOT_LEAP(x) macro to display a message that the user input year is not a leap year. LEAP_YEAR(x) macro is used to display message that the user input year is a leap year.

We use both NOT_LEAP(x) and LEAP_YEAR(x) macro names or macro templates inside LEAP(x) macro expansion.

We’re also using macro continuation(\) to break the line and continue writing the logic in next line in macro expansion of LEAP(x).

List of some leap years

2000
2004
2008
2012
2016
2020
2024
2028
2032
2036
2040
2044
2048

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

Swap 2 Numbers Using Macros: C Program

Today lets learn how to swap two integer numbers(using a temporary variable) using Macros in C.

Video Tutorial: Swap 2 Numbers Using Macros: C Program

[youtube https://www.youtube.com/watch?v=esQ-DmyPYYc]

YouTube Link: https://www.youtube.com/watch?v=esQ-DmyPYYc [Watch the Video In Full Screen.]

Source Code: Swap 2 Numbers Using Macros: C Program

#include<stdio.h>

#define SWAP(x, y, temp) temp = x; x = y; y = temp;

int main()
{
    int a, b, temp;

    printf("Enter 2 integer numbers\n");
    scanf("%d%d", &a, &b);

    printf("Before swapping: a = %d and b = %d\n", a, b);

    SWAP(a, b, temp);

    printf("After swapping: a = %d and b = %d\n", a, b);

    return 0;
}

Output:
Enter 2 integer numbers
20
50
Before swapping: a = 20 and b = 50
After swapping: a = 50 and b = 20

Logic To Swap Two Numbers

First value of a is transferred to temp;
Next value of b is transferred to a.
Next value of temp is transferred to b.

That’s how value of a and b are swapped using a temporary variable.

Note: Preprocessor replaces the macro template(SWAP(a, b, temp)) with its corresponding macro expansion(temp = x; x = y; y = temp;) before passing the source code to the compiler.

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert