Answer to Question #41309 in Java | JSP | JSF for solomon

Question

computes the sum of the following series.
Sum=1!+2!+3!+4!+........n!

Answer 1

#include <iostream>
long factorial(long n) {
    if ( n < 0 ) {
        return -1;
    }
    if ( n < 2 ) {
        return 1;
    } else {
        return n * factorial(n-1);
    }
}
int main() {
    int fact;
    long long unsigned sum = 0;
    std::cout << "Please enter N " << std::endl;
    std::cin >> fact;
    for ( long i = 1; i <= fact; i++) {
        sum += factorial(i);
    }
    std::cout << "The sum is " << sum << std::endl;
    return 0;
}