def printChar1(msg):
    """ potentially prints every character in the string"""
    for element in msg:
        print(element)
        
def printChar2(msg):
    l = len(msg)
    for i in range(l):
        print(msg[i])
        
def printChar3(msg):
    l = len(msg)
    for i in range(0,l):
        print(msg[i])
        
def sumOfDigits(n):
    s = str(n)
    if len(s) > 1:
        return int(s[0]) + sumOfDigits(int(s[1:]))
    else:
        return n
    
import math
def QuadraticSolver(a,b,c):
    """ Solves the equation ax^2 + bx + c = 0 using the quadratic solver """
    
    print(a,"x^2 + ",b,"x + ",c, " = 0")
    x1 = (-b + math.sqrt( b ** 2 - 4 * a * c) )/ (2 * a) 
    x2 = (-b - math.sqrt( b ** 2 - 4 * a * c) )/ (2 * a)
    
    #print("x1: ",x1)
    #print("x2: ",x2)
    
    return [x1, x2]

def print_list(L):
    """ Print every element in a list"""
    
    for element in L:
        print(element)
        
def print_list2(L):
    for i in range(len(L)):
        print(L[i])
        
def sum_list(L):
    sum = 0
    for num in L:
        sum += num
    
    return sum

def double_list(L):
    for i in range(len(L)):
        L[i] = L[i]*2
        
    return L



def double_list2(L):
    newL = list()
    #newL = []
    
    for item in L:
        newL.append(item*2)
        
    return(newL)

def double_list3(L):
    return [item * 2 for item in L]