# File: Erin/sumList.py
"""
original list myL =  [1, 3, -10, 2]
sum of the sequence =  -4
current list =  [1, 3, -10, 2]
tuple(myL) -> (1,3,-10,2) # List to tuple conversion
sum(1,2,3) -> 6 # sum() is Python function
"""
myL = [1, 3, 5, 2, 2]            #global variable my List

def sumSeq( L ):
    def sum2(a, b): return a + b #declare a function in a function
    return reduce(sum2, L, 0) 

def mysum(L):                   # sum with a for loop
    sum = 0
    for i in range(len(L)):
        sum = sum + L[i]
    return sum

def sumUp( n , L ):             # sum of a list with  recursion
    if (n == 0):
        return L[0]
    return L[n] + sumUp( n-1, L )

def main():
    print("original list myL= ", myL)
    #print("sum of the sequence = ", sumSeq( myL ))
    print("sum all from list =", sum(tuple(myL)))
    print("Sum of",myL," = ",mysum(myL))
    print("Sum of",myL," = ",sumUp(len(myL)-1, myL))
        
main()