Lecture21 categoriesof userdefinedfunctions.ppt

Categories of
User Defined Functions in ‘C’

Prakash Khaire
Lecturer, B V Patel Inst. of BMC & IT, Gopal
Vidyanagar
Prakash Khaire, B V Patel Inst. Of BMC &

*
Lecturer IT, Gopal Vidyanagar

Introduction
Introduction Functions are categorized based on the arguments are
●
passed or whether a value is returned or not
Category 1

Category 2
●Functions with no agruments and no return values.
●Functions with arguments and no return values.

Category 3 ●Functions with arguments and one return value.
●Functions with no arguments but return a vlues.

Category 4 ●Functions that return multiple values

Category 5

Recursion

*
Prakash Khaire,
Prakash Khaire, Lecturer B V Patel Inst. Of B V Patel Inst. Of BMC & Vidyanagar
BMC & IT, Gopal IT, Gopal Vidyanagar

Functions with no arguments and no return values
Introduction
●You do not pass data to the called function.
Category 1 ●function with no return type does not pass

Category 2 back data to the calling function.
●This type of function which does not return
Category 3
any value cannot be used in an expression
Category 4
it can be used only as independent
Category 5 statement.
Recursion

*
Prakash Khaire,

Introduction #include<stdio.h>
#include<conio.h> void main()
Category 1 void printline() {
{ clrscr();
Category 2 int i; printf("Welcome to function in C");
printf("n"); printline();
for(i=0;i<30;i++) printf("Function easy to learn.");
Category 3 {
printline();
printf("-");
Category 4 } getch();
printf("n"); }
Category 5 }

Recursion

*
Prakash Khaire,

Introduction

Category 1

Category 2

Category 3

Category 4

Category 5

Recursion

*
Prakash Khaire,

Functions with arguments and no return value
Introduction
●It accept data from calling function.
Category 1 ●you send data to the called function from

Category 2 calling function but you cannot send result
Category 3
data back to the calling function.
Category 4

Category 5

Recursion

*
Prakash Khaire,

Introduction #include<stdio.h> void main()
#include<conio.h> {
Category 1 void add(int x, int y) clrscr();
{ add(30,15);
Category 2 int result; add(63,49);
result = x+y; add(952,321);
printf("Sum of %d and %d is %d.nn",x,y, getch();
Category 3 result); }
}
Category 4

Category 5

Recursion

*
Prakash Khaire,

Introduction

Category 1

Category 2

Category 3

Category 4

Category 5

Recursion

*
Prakash Khaire,

Functions with arguments and return value
Introduction ●It can send arguments (data) from the calling function to the
called function
Category 1
●It wait for the result to be returned back from the called function

Category 2
back to the calling function
●This type of function is mostly used in programming world

Category 3 because it can do two way communications
●It can accept data as arguments as well as can send back data
Category 4 as return value
●The data returned by the function can be used later in our
Category 5 program for further calculations.
Recursion

*
Prakash Khaire,

Introduction #include<stdio.h> void main()
#include<conio.h> {
Category 1
int add(int x, int y) int z;
Category 2
{ clrscr();
int result; z = add(952,321);
Category 3 result = x+y; printf("Result %d.nn",add(30,55));
return(result); printf("Result %d.nn",z);
Category 4 } getch();
}
Category 5

Recursion

*
Prakash Khaire,

Introduction

Category 1

Category 2

Category 3

Category 4

Category 5

Recursion

*
Prakash Khaire,

Functions with no arguments but returns value
Introduction
●A function which does not take any
Category 1 argument but only returns values to the
Category 2 calling function.
●The best example of this type of function is
Category 3
“getchar()” library function which is declared
Category 4
in the header file “stdio.h”.
Category 5

Recursion

*
Prakash Khaire,

void main()
#include<conio.h>
Category 1 {
int send()
int z;
{
Category 2 clrscr();
int no1;
z = send();
Category 3 printf("Enter a no : ");
printf("nYou entered : %d.", z);
scanf("%d",&no1);
getch();
Category 4 return(no1);
}
}
Category 5

Recursion

*
Prakash Khaire,

Introduction

Category 1

Category 2

Category 3

Category 4

Category 5

Recursion

*
Prakash Khaire,

Functions that return multiple values
Introduction
●To send values to the called function, in the
Category 1 same way we can also use arguments to
Category 2 send back information to the calling function
●The arguments that are used to send back
Category 3
data are called Output Parameters.
Category 4

Category 5

Recursion

*
Prakash Khaire,

Functions that return multiple values
void main()
#include<conio.h>
Category 1 {
void calc(int x, int y, int
int a=20, b=11, p,q;
*add, int *sub)
Category 2 clrscr();
{
calc(a,b,&p,&q);
Category 3 *add = x+y;
printf("Sum = %d, Sub = %d",p,q);
*sub = x-y;
getch();
Category 4 }
}
Category 5

Recursion

*
Prakash Khaire,

Recursion
Introduction
●A function calling itself again and again to
Category 1
compute a value
Category 2 ●Normally function are called by main

Category 3 function or by some another function
●But in recursion the same function is called
Category 4
by itself repeatedly
Category 5

Recursion

*
Prakash Khaire,

Closing
Introduction
int fact(int k) 1st call -> return(4 * fact(4-1));
{ return(4 * fact(3));
Category 1 if(k==0) 2nd call -> return(3 * fact(3-1));
{ return(3 * fact(2));
Category 2 return(1); 3rd call -> return(2 * fact(2-1));
} return(2 * fact(1));
Category 3 else
{
Category 4
return(k * fact(k-1));
}
}
Category 5

Recursion

*
Prakash Khaire,

Use of Recursive Function
Introduction
●Recursive functions are written with less
Category 1
number of statements compared functions
Category 2 ●Recursion is effective where terms are

Category 3 generated successively to compute a value
Category 4

Category 5

Recursion

*
Prakash Khaire,

Lecture21 categoriesof userdefinedfunctions.ppt

Recommended

More Related Content

What's hot (20)

Viewers also liked (20)

Similar to Lecture21 categoriesof userdefinedfunctions.ppt (6)

More from eShikshak (15)

Recently uploaded (20)

Lecture21 categoriesof userdefinedfunctions.ppt