Adding factorials. Given an integer n, calculate and print the sum of the factorials from 1! to n!:

n = int(input()) sum_factorials = 0 current_factorial = 1 for i in range(1, n + 1): current_factorial *= i sum_factorials += current_factorial print(sum_factorials) 
 Reading Input:
 The
input()
function reads a line of text from the user.
 The
int()
function converts this input to an integer and stores it in the variable n
.
 Initialize the Sum and Current Factorial:
sum_factorials = 0
current_factorial = 1
 A variable
sum_factorials
is initialized to 0. This will be used to store the sum of the factorials.
 A variable
current_factorial
is initialized to 1. This will be used to compute each factorial incrementally.
 Calculate Sum of Factorials:
for i in range(1, n + 1):
current_factorial *= i
sum_factorials += current_factorial
 A
for
loop iterates over the range from 1 to $n$ (inclusive).
 In each iteration, the current number $i$ is multiplied with
current_factorial
to compute the factorial incrementally.
 The
current_factorial
is then added to sum_factorials
.
 Print the Sum of Factorials:
 Finally, the
print()
function outputs the value of sum_factorials
.