'''Write a simple parser that will parse and run Deadfish.

Deadfish has 4 commands, each 1 character long:

i increments the value (initially 0)
d decrements the value
s squares the value
o outputs the value into the return array
Invalid characters should be ignored.

parse("iiisdoso")  ==>  [8, 64]'''

def parse(data):
    arr = []
    x = 0
    for i in data:
        if i == 'i':
            x +=1
        elif i == 's':
            x = x**2
        elif i == 'd':
            x -=1
        elif i == 'o':
            arr.append(x)
    return arr
