1)WAP to get factorial value of a number using function.It returns value with no parameter.

in turboc++
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//program to find factorial value of a number using function with returning value.
#include<stdio.h>                      //header file
#include<conio.h>
int factorial();                          // function prototype/declaration with return type int.
int main()                              //main function
{
printf("value=%d",factorial());// function calling and printing output.
getch();
return 0;                                       //returns 0 value
}
int factorial()                             // function body line ; also called function definition
{
 int i,n,facto=1;                    // variable declaration with 1 initialization
printf("enter a number\n");    //message display to input a number
scanf("%d",&n);                //gets input
for(i=1;i<=n;i++)       //loop running from 1 to n with increment 1 each time
{
       facto=facto*i;        //  multiplication of numbers repetitively
}
  return facto;         //returning facto value
}



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in codeblocks
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//program to find factorial value of a number using function with returning value.
#include<stdio.h>                      //header file
int factorial();                          // function prototype/declaration with return type int.
int main()                              //main function
{
printf("value=%d",factorial());// function calling and printing output.
return 0;                                       //returns 0 value
}
int factorial()                             // function body line ; also called function definition
{
 int i,n,facto=1;                    // variable declaration with 1 initialization
printf("enter a number\n");    //message display to input a number
scanf("%d",&n);                //gets input
for(i=1;i<=n;i++)       //loop running from 1 to n with increment 1 each time
{
       facto=facto*i;        //  multiplication of numbers repetitively
}
  return facto;         //returning facto value
}