Chapter 7 : The C Preprocessor (Let us C)

(a) Write down macro definitions for the following:
1. To test whether a character entered is a small case letter or not.
2. To test whether a character entered is a upper case letter or not.
3. To test whether a character is an alphabet or not. Make use of the macros you defined in (1) and (2) above.
4. To obtain the bigger of two numbers.

// Let Us C (Chapter 7 : The C Preprocessor) : Program-1
/* Write down macro definitions for the following:
1. To test whether a character entered is a small case letter or not.
2. To test whether a character entered is a upper case letter or not.
3. To test whether a character is an alphabet or not. Make use of the macros you defined in (1) and (2) above.
4. To obtain the bigger of two numbers */
#include<stdio.h>
#include<conio.h>
#define SMALL(ch) ((ch>=97)&&(ch<=122))
#define CAP(ch) ((ch>=65) && (ch<=90))
#define ALPHA(ch) (SMALL(ch)||CAP(ch))
#define BIGGER(a,b) (a>b)?a:b
void main()
{
    unsigned int Choice;
    int a,b,bigger;
    char c;
    clrscr();
    printf("1:To test whether a character entered is a small case letter or not\n");
    printf("2:To test whether a character entered is a upper case letter or not\n");
    printf("3:To test whether a character is an alphabet or not\n");
    printf("4:To obtain the bigger of two numbers\n");
    printf("Enter your choice: ");
    scanf("%d",&Choice);
    switch(Choice)
    {
        case 1:
            printf("Enter a character: ");
            scanf(" %c",&c); //space to discard whitespace before char
            if(SMALL(c))
                printf("%c is a Small case letter",c);
            else
                printf("%c is Not a Small case letter",c);
            break;

        case 2:
            printf("Enter a character: ");
            scanf(" %c",&c); //space to discard whitespace before char
            if(CAP(c))
                printf("%c is an Upper case letter",c);
            else
                printf("%c is Not an Upper case letter",c);
            break;

        case 3:
            printf("Enter a character: ");
            scanf(" %c",&c); //space to discard whitespace before char
            if(ALPHA(c))
                printf("%c is an Alphabet",c);
            else
                printf("%c is Not an Alphabet",c);
            break;

        case 4:
            printf("Enter 2 numbers: ");
            scanf("%d%d",&a,&b);
            bigger = BIGGER(a,b);
            printf("%d is Bigger",bigger);
            break;

        default:
            break;
    }
}

(b) Write macro definitions with arguments for calculation of area and perimeter of a triangle, a square and a circle. Store these macro definitions in a file called "areaperi.h". Include this file in your program, and call the macro definitions for calculating area and perimeter for different squares, triangles and circles.

// Let Us C (Chapter 7 : The C Preprocessor) : Program-2
/* Write macro definitions with arguments for calculation of area and perimeter of a triangle, a square and 
a circle. Store these macro definitions in a file called "areaperi.h". Include this file in your program, and 
call the macro definitions for calculating area and perimeter for different squares, triangles and circles. */
/********************************* areaperi.h **********************************/
//Create file areaperi.h. Save it to the same folder where .c file have been saved. compile it first and include it in .c file
#include <math.h>
#ifndef WHATEVER_H_INCLUDED
/*They avoid including the same header file twice in the same compilation*/
#define WHATEVER_H_INCLUDED
#define PI 3.14
#define TRI_AREA(a,b,c,s)    (sqrt(s*(s-a)*(s-b)*(s-c)))
#define TRI_PERI(a,b,c)        (a+b+c)
#define SQ_AREA(s)        (s*s)
#define SQ_PERI(s)        (4*s)
#define CIRC_AREA(r)        (PI*r*r)
#define CIRC_PERI(r)        (2*PI*r)
#endif

 /********************************* .c file **********************************/
#include<stdio.h>
#include<conio.h>
#include "areaperi.h" /* inclusion header file */

void main()
{
    int Choice;
    float a,b,c,s,tri_area,tri_peri,sq_area,sq_peri,circ_area,circ_peri;
    clrscr();
    printf("Program to calculate Area & Perimeter\n");
    printf("1: TRIANGLE\n");
    printf("2: SQUARE\n");
    printf("3: CIRCLE\n");
    printf("Enter your choice: ");
    scanf("%d",&Choice);
    switch(Choice)
    {
        case 1:
        printf("Enter 3 sides of the Triangle: ");
        scanf("%f%f%f,&a,&b,&c");
        s = (a+b+c)/2;
        tri_area = TRI_AREA(a,b,c,s);
        tri_peri = TRI_PERI(a,b,c);
        printf("\nArea of Triagnle = %0.2f",tri_area);
        printf("\nPerimeter of Triagnle = %0.2f",tri_peri);
        break;

        case 2:
        printf("Enter sides of the Square: ");
        scanf("%f,&a");
        sq_area = SQ_AREA(a);
        sq_peri = SQ_PERI(a);
        printf("\nArea of Square = %0.2f",sq_area);
        printf("\nPerimeter of Square = %0.2f",sq_peri);
        break;

        case 3:
        printf("Enter radius of the circle: ");
        scanf("%f,&a");
        circ_area = CIRC_AREA(a);
        circ_peri = CIRC_PERI(a);
        printf("\nArea of Circle = %0.2f",circ_area);
        printf("\nPerimeter of Circle = %0.2f",circ_peri);
        break;
    }
}

(c) Write down macro definitions for the following:
1. To find arithmetic mean of two numbers.
2. To find absolute value of a number.
3. To convert a uppercase alphabet to lowercase.
4. To obtain the bigger of two numbers.

// Let Us C (Chapter 7 : The C Preprocessor) : Program-3
/* Write down macro definitions for the following:
1. To find arithmetic mean of two numbers.
2. To find absolute value of a number.
3. To convert a uppercase alphabet to lowercase.
4. To obtain the bigger of two numbers */
#include<stdio.h>
#include<conio.h>
#define AM(a,b)     ((a+b)/2)
#define ABS(a)      (a>0)?a:(a*(-1))
#define UtoL(ch)    ((ch>64)&&(ch<91))?(ch+32):0
#define BIGGER(a,b) ((a>b)?a:b)
void main()
{
    int Choice,num,abs;
    float a,b,am,bigger;
    char ch,utol;
    clrscr();
    printf("1: Arithmetic Mean\n");
    printf("2: Absolute Value\n");
    printf("3: UpperCase to LowerCase\n");
    printf("4: Bigger of 2 numbers\n");
    printf("Enter your choice: ");
    scanf("%d",&Choice);
    switch(Choice)
    {
        case 1:
        printf("Enter 2 numbers: ");
        scanf("%f%f",&a,&b);
        am = AM(a,b);
        printf("\nArithmetic Mean of %0.2f & %0.2f = %0.2f",a,b,am);
        break;

        case 2:
        printf("Enter a numbers: ");
        scanf("%d",&num);
        abs = ABS(num);
        printf("\nAbsolute value of %d is %d",num,abs);
        break;

        case 3:
        printf("Enter an UpperCae alphabet: ");
        scanf(" %c",&ch); //space included to discard any whitespace
        utol = UtoL(ch);
        if(utol)
            printf("\n%c in Uppercase = %c in Lowercase",ch,utol);
        else
            printf("You did not Enter Uppercase alphabet");
        break;

        case 4:
        printf("Enter 2 numbers: ");
        scanf("%f%f",&a,&b);
        bigger = BIGGER(a,b);
        printf("\n%0.2f is bigger",bigger);
        break;
    }
}

(d) Write macro definitions with arguments for calculation of Simple Interest and Amount. Store these macro definitions in a file called "interest.h". Include this file in your program, and use the macro definitions for calculating simple interest and amount.

// Let Us C (Chapter 7 : The C Preprocessor) : Program-4
/* Write macro definitions with arguments for calculation of Simple Interest and Amount. Store these macro 
definitions in a file called "interest.h". Include this file in your program, and use the macro definitions 
for calculating simple interest and amount. */
#include<stdio.h>
#include<conio.h>
#include"interest.h"   /* inclusion of header file */
void main()
{
    int p,r,t,a;
    float si;
    clrscr();
    printf("Program to calculate Simple Interest\n");
    printf("Enter the Principle Amount:  ");
    scanf("%d",&p);
    printf("Enter the rate of interest(per year):  ");
    scanf("%d",&r);
    printf("Enter the time(in years):  ");
    scanf("%d",&t);
    si=INTEREST(p,r,t);
    a=AMOUNT(p,si);
    printf("\nsimple interest = %f\namount = %d",si,a);
}

/********************************* interest.h **********************************/
Create file interest.h. Save it to the same folder where .c file have been saved. compile it first
& include it in .c file 

#define INTEREST(x,y,z) (x*y*z/100)
#define AMOUNT(x,y) (x+y)