from functools import reduce

def str2float(s):
    return float(s)

def calc(exp):
    ss = exp.split('+')
    return reduce(lambda acc, x: acc + x, map(str2float, ss))

def main():
    r = calc('100 + 200 + 345')
    print('100 + 200 + 345 =', r)
    r= calc('99 + 88 + 7.6')
    print('99 + 88 + 7.6 =', r)
   
main()