#include <iostream>
using namespace std;
int main()
{
int i, number=0, factorial=1;
// User input must be an integer number between 1 and 10
while(number<1 number>10)
{
cout << "Enter integer number (1-10) = ";
cin >> number;
}
// Calculate the factorial with a FOR loop
for(i=1; i<=number; i++)
{
factorial = factorial*i;
}
// Output result
cout << "Factorial = " << factorial << endl;
A recursive function is one that calls upon itself until a given result in the original call is met. Take a look at this example. Program Recursion; Uses crt; Var number:longint; Function Factorial(number:longint):longint; Begin if number > 0 then factorial:=number*factorial(number-1) else factorial:=1; End; Begin clrscr; readln(number); writeln(factorial(number)); readln; End. Note how the function factorial calls itself.
' Iterative solution Function iterativeFactorial(ByVal n As Long) As Long Dim factorial As Long = 1 For i As Long = 1 To n factorial *= i Next Return factorial End Function ' Recursive solution Function recursiveFactorial(ByVal n As Long) As Long If n <= 1 Then Return n End If Return n * recursiveFactorial(n - 1) End Function
The factorial f(n) = n * (n-1) * (n-2) * .. 1. For example factorial 5 (written as 5!) = 5 x 4 x 3 x 2 x 1 = 120. The function below returns the factorial of the parameter n. int factorial( int n) { if (n==1) return 1 else return n* factorial( n-1) ; }
// Iterative solution public static final long iterativeFactorial(final long n) { long factorial = 1; for (long i = 1; i <= n; i++) { factorial *= i; } return factorial; } // Recursive solution public static final long recursiveFactorial(final long n) { if (n <= 1) { return n; } return n * recursiveFactorial(n - 1); } // Arbitrary length solution - may take a while, but works on any positive number. public static final BigInteger factorial(final BigInteger n) { BigInteger factorial = BigInteger.ONE; for (BigInteger i = BigInteger.ONE; i.compareTo(n) <= 0; i = i.add(BigInteger.ONE)) { factorial = factorial.multiply(i); } return factorial; }
since factorial is for example , the factorial of 5 = 5 (5-1)(5-2)(5-3)(5-4) that means the last number to subtract from 5 is 4 , which is (n-1) ie the factorial of any number is (n-0)(.............)(n-(n-1)) to write this , 5 REM to calculate the factorial of any number 6 DIM fac AS INTEGER LET fac = 1 10 INPUT "enter the number to find its factorial "; a ' variable a 15 FOR b = 0 TO (a-1) 'numbers that will be subtracted from the " a" 20 c= a -b 'each number in the factorial calculation 25 fac = fac * c 'to compute each multiplication in the factorial 30 NEXT b 35 PRINT 'to leave a line 40 PRINT fac 45 END note this due to some unattained raesons works for numbers 0 to 7
A recursive function is one that calls upon itself until a given result in the original call is met. Take a look at this example. Program Recursion; Uses crt; Var number:longint; Function Factorial(number:longint):longint; Begin if number > 0 then factorial:=number*factorial(number-1) else factorial:=1; End; Begin clrscr; readln(number); writeln(factorial(number)); readln; End. Note how the function factorial calls itself.
' Iterative solution Function iterativeFactorial(ByVal n As Long) As Long Dim factorial As Long = 1 For i As Long = 1 To n factorial *= i Next Return factorial End Function ' Recursive solution Function recursiveFactorial(ByVal n As Long) As Long If n <= 1 Then Return n End If Return n * recursiveFactorial(n - 1) End Function
int factorial(int n) { int i; int f=1; for(i=2;i<=n;++i) f*=i; return f; }
Factorial for number N is N x N-1 x N-2 X N- (N-1). e.g. if you need to calculate factorial for 5 then compute 5 x 4 x 3 x 2 x 1.
A recursive definition is any definition that uses the thing to be defined as part of the definition. A recursive formula, or function, is a related formula or function. A recursive function uses the function itself in the definition. For example: The factorial function, written n!, is defined as the product of all the numbers, from 1 to the number (in this case "n"). For example, the factorial of 4, written 4!, is equal to 1 x 2 x 3 x 4. This can also be defined as follows: 0! = 1 For any "n" > 0, n! = n x (n-1)! For example, according to this definition, the factorial of 4 is the same as 4 times the factorial of 3. Try it out - apply the recursive formula, until you get to the base case. Note that a base case is necessary; otherwise, the recursion would never end.
The factorial f(n) = n * (n-1) * (n-2) * .. 1. For example factorial 5 (written as 5!) = 5 x 4 x 3 x 2 x 1 = 120. The function below returns the factorial of the parameter n. int factorial( int n) { if (n==1) return 1 else return n* factorial( n-1) ; }
// Iterative solution public static final long iterativeFactorial(final long n) { long factorial = 1; for (long i = 1; i <= n; i++) { factorial *= i; } return factorial; } // Recursive solution public static final long recursiveFactorial(final long n) { if (n <= 1) { return n; } return n * recursiveFactorial(n - 1); } // Arbitrary length solution - may take a while, but works on any positive number. public static final BigInteger factorial(final BigInteger n) { BigInteger factorial = BigInteger.ONE; for (BigInteger i = BigInteger.ONE; i.compareTo(n) <= 0; i = i.add(BigInteger.ONE)) { factorial = factorial.multiply(i); } return factorial; }
since factorial is for example , the factorial of 5 = 5 (5-1)(5-2)(5-3)(5-4) that means the last number to subtract from 5 is 4 , which is (n-1) ie the factorial of any number is (n-0)(.............)(n-(n-1)) to write this , 5 REM to calculate the factorial of any number 6 DIM fac AS INTEGER LET fac = 1 10 INPUT "enter the number to find its factorial "; a ' variable a 15 FOR b = 0 TO (a-1) 'numbers that will be subtracted from the " a" 20 c= a -b 'each number in the factorial calculation 25 fac = fac * c 'to compute each multiplication in the factorial 30 NEXT b 35 PRINT 'to leave a line 40 PRINT fac 45 END note this due to some unattained raesons works for numbers 0 to 7
Let's take the example of finding the factorial of a number (of a positive integer). The factorial of N is N * (N-1) * (N-2) * (N-3) ... * 3 * 2 *1 It is the product of all integers between that number (including that number) and 1. For example, factorial 2 = 2*1 = 2 factorial 3 = 3*2*1 = 6 factorial 4 = 4*3*2*1= 24 Now you define a recursive function Fac (N) as Fac (N) = Fac (N-1) * N, with Fac(1) predefined as 1. Thus, Fac(N-1) = Fac(N-2) * (N-1) and Fac(N-2) = Fac(N-3) * (N-2) and thus recursion takes over until such time fac(1) needs to be evaluated. We know the value of Fac(1) which is set as 1. Thus we can evaluate Factorial(N) using recursion.
double factorial(double N){double total = 1;while (N > 1){total *= N;N--;}return total; // We are returning the value in variable title total//return factorial;}int main(){double myNumber = 0;cout > myNumber;cout
Pseudo code+factorial
Such a method could be: public int NumberOfDigits(int num) { num = num/10; if( num == 0) return 1; return ( 1+NumberOfDigits(num) ); }