17-10-2011 (1st) Function Calls

/*Example to understand calling of functions*/

#include<stdio.h>

#include<conio.h>

void abc();

void xyz();

void mno();

main()

{

      printf("I am in main()\n");

      abc();

      printf("Now I am back in main()");

      getche();

      return 0;

}

void abc()

{

     printf("Now I am in abc()\n");

     xyz();

     mno();

}

void xyz()

{

     printf("Now I am in xyz()\n");

}

void mno()

{

     printf("Now I am in mno()\n");

}

17-10-2011 Sum Using a function

/*program uses a function to add two digits*/

#include<stdio.h>

#include<conio.h>

int sum(int,int);

main()

{

      int dig1,dig2,result;

      dig1 = 10;

      dig2 =5;

     

      /*calling function and storing rturned value in variable result*/

      result = sum(dig1,dig2);

      printf("%d + %d = %d",dig1,dig2,result);

      getche();

      return 0;

}

/*Defining functions*/

int sum(int digi1, int digi2)

{

    int add;

    add = digi1 + digi2;

    return add;

}

     

     

     

17-10-2011 Sum Using a function(function changes values before adding)

/*program uses a function to add two digits but function changes passed values before adding them*/

#include<stdio.h>

#include<conio.h>

int sum(int,int);

main()

{

      int dig1,dig2,result;

      dig1 = 10;

      dig2 =5;

      /*calling function and storing rturned value in variable result*/

      result = sum(dig1,dig2);

      printf("%d",result);

      getche();

      return 0;

}

/*Defining functions*/

int sum(int digi1, int digi2)

{

    digi1 =2;

    digi2 =3;

    int add;

    add = digi1 + digi2;

    return add;

}

     

     

     

17-10-2011 Division Using a function

/*program uses a fubction to divide one digit by another*/

#include<stdio.h>

#include<conio.h>

/*declaring function*/

float div(float,float);

main()

{

      float dig1=0,dig2=0,result=0;

      printf("Please enter a number: ");

      scanf("%f",&dig1);

     

       while(dig2 == 0)

       {

                  printf("\n\n\nNow enter a number to divide first digit: ");

                  scanf("%f",&dig2);

                  if(dig2==0)

                  {

                       printf("\tWarning!\nDenominator can not be zero.");

                   }

                 

       }

       /*calling function and storing rturned value in variable result*/

      result = div(dig1,dig2);

      printf("%f / %f = %f",dig1,dig2,result);

      getche();

      return 0;

}

/*Defining function*/

float div(float digi1, float digi2 )

{

    float opert;

    opert = digi1 / digi2;

    return opert;

}

     

     

     

17-10-2011 Cheking of Greatest number Using a function

/* This program takes three integers from user, calls a function to compares which one is greatest

and shows results inside that function.*/

#include<stdio.h>

#include<conio.h>

/*declaring function*/

void check(int, int, int);

int main ()

{

    /*declaring veriables*/

    int num11, num22, num33;

  

    /*prompt to take the input*/

    printf("Please enter three integers, remember pressing enter after every one: \n");

   

    /*taking input*/

    scanf("%d%d%d",&num11,&num22,&num33);

    check(num11, num22,num33);

    getche();

    return 0;

}

/*Defining function*/

void check(int num1, int num2,int num3)

{

    /*comparison and printing results*/

    printf("\n\nResult: \n");

    printf("___________\n\n");

    if (num1 > num2 && num1 > num3)

    {

         printf("%d is greatest!",num1);

    }

    else if (num2 > num1 && num2 > num3)

    {

         printf("%d is greatest!",num2);

    }

    else if (num3 > num1 && num3 > num2)

    {

         printf("%d is greatest!",num3);

    }

    else if (num1 == num2 && num1 == num3)

    {

         printf("All of the given digits are equal.");

    }

    else

    {

         printf("This is some other case not defined in the program!");

    }

   

}

17-10-2011 Calculator (Calls Functions to Do Operations)

/* A simple calculator which calls function to do operations*/

#include <stdio.h>

#include <conio.h>

/*declaring function*/

float add(float,float);

float sub(float,float);

float mult(float,float);

float div(float,float);

int main()

{

    char exit = ' ';

    do

        {

               

            float dig1 = 0 , dig2 = 0 ;

            char opert;

            printf("Please enter first digit: ");

            scanf("%f",&dig1);

            printf("\n\nNow enter operation to perform: ");

            scanf("%c",&opert);

            opert=getche();

                  

                   /*if operation is division then implementing cheks and conditions to stop entering denominator as zero*/

            if (opert=='/')

            {

                while(dig2 == 0)

                {

                printf("\n\n\nNow enter 2nd the digit: ");

                scanf("%f",&dig2);

                    if(dig2==0)

                    {

                               printf("\tWarning!\nDenominator can not be zero.");

                    }

                }

            }

            else

            {

                printf("\n\n\nNow enter 2nd the digit: ");

                scanf("%f",&dig2);

            }

                           

            /*Checking operation and calling function related to operation*/       

            switch (opert)

            {

                case '+':

                add(dig1,dig2);

                break;

                case '-':

                sub(dig1,dig2); 

                break;

               

                case '*':    

                mult(dig1,dig2);

                break;

                                

                case '/':    

                div(dig1,dig2);

                break;

                default :

                printf("\t\n\nWarning!\n Wrong operation entered.");

            }

            exit = ' ';

            /*To continue or exit*/

            while(exit !='e' && exit != 'c' && exit !='E' && exit != 'C')

            {

                printf("\n\nEnter 'e' to exit or 'c' to continue using program: ");

                scanf("%c",&exit);

                exit = getche();

                printf("\n\n");

            }

        }

        while (exit != 'e' && exit != 'E');   

   

    getche();

    return 0;

}

/*Defining functions*/

/*addition function*/

float add(float digi1add, float digi2add )

{

    printf("\n\n%f + %f = %f\n\n\n",digi1add, digi2add, digi1add + digi2add);

}

/*subtraction function*/

float sub(float digi1sub, float digi2sub )

{

    printf("\n\n%f - %f = %f\n\n\n",digi1sub, digi2sub, digi1sub - digi2sub);

}

/*multiplication function*/

float mult(float digi1mul, float digi2mult )

{

     printf("\n\n%f x %f = %f\n\n\n",digi1mul, digi2mult, digi1mul * digi2mult );

}

/*division function*/

float div(float digi1div, float digi2div )

{

     

    printf("\n\n%f / %f = %f\n\n\n",digi1div, digi2div, digi1div / digi2div);

}