Factorial program c using recursive function in C with while loop - c

Question

Factorial program using recursion in c with while loop.In this program once the execution reaches the function return statement it will not go back to the function call. Instead,it executes the function repeatedly. can anybody please tell me what's wrong in this program.
#include<stdio.h>
int fact(int n)
{
int x=1;
while(n>1)
{
x=n*fact(n-1);
}
return(x);
}
void main()
{
int n,fact1;
scanf("%d",&n);
fact1=fact(n);
printf("%d",fact1);
}

Answer 1

The reason that your program gets into an infinite loop is that the loop
while (n > 1)
x = n * fact(n-1);
never decrements n. Since n never decreases, the program will never leave the loop. Peter is correct in the comments: change the while to an if, and you will have a factorial function that handles all positive parameters correctly. However, even after changing while to if, your fact won't have the property that fact(0) == 1, as is required for a correct factorial function.

Answer 2

This
while(n>1)
is causing the looping. You don't change n inside the loop, so the loop is infinite.
Change while to if.

Answer 3

This is the method of factorial:
public int fact(int n)
{
if (n < 1)
{
return 1;
}
else
{
return n * fact(n - 1);
}
}

Answer 4

#include <stdio.h>
#include <stdlib.h>
/** main returns int, use it! */
int main(int argc, char **argv)
{
if (argc <= 2) {
if (argv) argc = atoi(argv[1] );
else return argc;
}
argc *= main (argc-1, NULL);
if (argv) {
printf("=%d\n", argc);
return 0;
}
return argc;
}

Answer 5

/*
Write a C++ Program to input a positive number,
Calculate and display factorial of this number
by recursion.
*/
#include<iostream.h>
#include<conio.h>
long factorial(int n);
void main()
{
clrscr();
int number, counter;
label1:
cout<<"\n Enter the Number = ";
cin>>number;
if ( number < 0)
{
cout<<"\n Enter a non negative number, please!";
goto label1;
}
cout<<"\n\n ----------- Results ------------";
cout<<"\n\n The Factorial of the number "<<number<<"\n is "<<factorial(number);
getch();
}
long factorial(int n)
{
if ( n == 0 )
return 1;
else
return n * factorial(n-1);
}

Answer 6

You can use the simple approach using recursion
#include <stdio.h>
int fact(int n)
{
if(n==1)
return 1;
else
return n * fact(n-1);
}
int main()
{
int f;
f = fact(5);
printf("Factorial = %d",f);
return 0;
}
Read it more C program to find factorial using recursion

Answer 7

/*several versions of a factorial program.*/
#include<stdio.h>
int main()
{
int n;
long factorial;
printf("Compute the factorial of what number? ");
scanf("%d", &n);
factorial = 1L;
while(n > 0)
factorial *= n--;
printf("The factorial is %ld\n", factorial);
return 0;
}
#include<stdio.h>
/*the same, but counting up to n instead of down to 0*/
int main()
{
register int count;
int n;
long factorial;
printf("Compute the factorial of what number? ");
scanf("%d", &n);
factorial = 1L;
count = 1;
while(count <= n)
factorial *= count++;
printf("%d! = %ld\n", n, factorial);
return 0;
}
#include<stdio.h>
/*an equivalent loop using 'for' instead of 'while'*/
int main()
{
register int count;
int n;
long factorial;
printf("Compute the factorial of what number? ");
scanf("%d", &n);
for(factorial = 1L, count = 1; count <= n; count++)
factorial *= count;
printf("%d! = %ld\n", n, factorial);
return 0;
}

Answer 8

/*WAP to find factorial using recursion*/
#include<stdio.h>
#include<stdlib.h>
int fact1=1;
int fact(int no)
{
fact1=fact1*no;
no--;
if(no!=1)
{
fact(no);
}
return fact1;
}
int main()
{
int no,ans;``
system("clear");
printf("Enter a no. : ");
scanf("%d",&no);
ans=fact(no);
printf("Fact : %d",ans);
return 0;
}

Answer 9

Factorial program using recursion in C with while loop.
int fact(int n)
{
int x=1;
while(n>=1)
{
return(n*fact(n-1));
}
return(1);
}

Answer 10

You can use this approach.
int factorial(int a)
{
while(a>1)
{
return a*factorial(a-1);
}
return 1;
}