Question

Написать программу на С++. Написать подпрограмму, которая принимает один аргумент и выводит на экран факториал переданного ей числа.

Answer 1

#include <iostream>
using namespace std; 

void fac(int n) {
   int s=1;  
   for (int i=1; i<=n; i++) s*=i;
   cout<<s<<endl;
}    

int main() {   
    int n;
    cout<<"number: ";  cin>>n;
    fac(n);
   system("pause");
    return 0;
}

Answer 2

Writing a C++ Program to Calculate Factorial

To write a C++ program that calculates the factorial of a given number, you can follow the steps below.

1. Include Necessary Libraries: - Include the necessary libraries for input/output operations and mathematical calculations.

   #include 
   using namespace std;
   

2. Define the Main Function: - Define the main function where the program execution begins.

   int main() {
       // Program logic will go here
       return 0;
   }
   

3. Accept User Input: - Accept the input from the user, which is the number for which the factorial needs to be calculated.

   int num;
   cout << "Enter a number: ";
   cin >> num;
   

4. Calculate the Factorial: - Write a loop to calculate the factorial of the input number.

   int factorial = 1;
   for (int i = 1; i <= num; i++) {
       factorial *= i;
   }
   

5. Display the Result: - Output the factorial of the input number.

   cout << "Factorial of " << num << " = " << factorial << endl;
   

Putting it all together, the complete C++ program to calculate the factorial of a given number looks like this:

#include 
using namespace std;

int main() {
    int num;
    cout << "Enter a number: ";
    cin >> num;

int factorial = 1;
    for (int i = 1; i <= num; i++) {
        factorial *= i;
    }

cout << "Factorial of " << num << " = " << factorial << endl;

return 0;
}

This program prompts the user to enter a number, calculates its factorial, and then displays the result.