{
if (n == 0)
return 1;
else
return (n * (factorial (n-1)));
}
The main logic of the factorial calculation using recursion can be described as follows:
1. The function takes an input parameter 'n' which represents the number for which the factorial is to be calculated.
2. The function checks if the value of 'n' is equal to 0. If it is, then it means we have reached the base case of the factorial calculation, and the function returns 1. This is because the factorial of 0 is defined as 1.
3. If 'n' is not equal to 0, then the function recursively calls itself with the argument 'n-1'. This recursive call calculates the factorial of the number 'n-1'.
4. The result of the recursive call is multiplied by 'n' and returned as the final result of the factorial calculation.
In summary, the logic uses recursion to break down the factorial calculation into smaller subproblems by repeatedly calling the factorial function with a decreasing value of 'n' until it reaches the base case of 0. The intermediate results are multiplied together to calculate the factorial of the original input number 'n'.
Factorial Using Loop
for(i=1;i<=number;i++){
fact=fact*i;
or,
i = n;
while (i != 0)
{
a = a * i;
i--;
}
The main logic in both examples is to calculate the factorial of a given number using a loop.
In the first example, a for loop is used. The loop starts with initializing a variable `i` to 1. It continues iterating as long as `i` is less than or equal to the given number. In each iteration, the `fact` variable is multiplied by `i` and stored back into `fact`. After each iteration, `i` is incremented by 1. This process continues until `i` exceeds the given number. At the end of the loop, the `fact` variable will contain the factorial of the given number.
In the second example, a while loop is used. The loop starts with initializing a variable `i` to the given number. It continues iterating as long as `i` is not equal to 0. In each iteration, the `a` variable is multiplied by `i` and stored back into `a`. After each iteration, `i` is decremented by 1. This process continues until `i` becomes 0. At the end of the loop, the `a` variable will contain the factorial of the given number.
Both examples achieve the same result of calculating the factorial using a loop, but they use slightly different loop structures.
