English numerals to integers (iterative function)

Question

Background

This stems from the kata (challenge) parseInt (reloaded). In theory, "nine hundred ninety-nine thousand nine hundred and ninety-nine" returns 999999—this is working now, but shorter cases like "two thousand" now fail. Note that I was trying recursion but now have resorted to iteration.

The Issue

The conditions for adding or multiplying to the result or the case with one number and multiple powers, e.g. "nine hundred thousand" in "one million nine hundred thousand" is poorly defined.

The Code

numbers = {'zero':0,'one':1,'two':2,'three':3,'four':4,'five':5,'six':6,'seven':7,'eight':8,'nine':9,'ten':10,'eleven':11,'twelve':12,'thirteen':13,'fourteen':14,'fifteen':15,'sixteen':16,'seventeen':17,'eighteen':18,'nineteen':19,'twenty':20,'thirty':30,'forty':40,'fifty':50,'sixty':60,'seventy':70,'eighty':80,'ninety':90,'eighty-six': 86, 'thirty-one': 31, 'forty-three': 43, 'forty-two': 42, 'fifty-eight': 58, 'sixty-seven': 67, 'thirty-two': 32, 'thirty-five': 35, 'seventy-nine': 79, 'thirty-four': 34, 'fifty-seven': 57, 'twenty-nine': 29, 'eighty-nine': 89, 'ninety-four': 94, 'seventy-eight': 78, 'ninety-one': 91, 'forty-one': 41, 'sixty-two': 62, 'twenty-eight': 28, 'eighty-eight': 88, 'seventy-seven': 77, 'forty-seven': 47, 'eighty-five': 85, 'eighty-three': 83, 'fifty-two': 52, 'eighty-two': 82, 'fifty-five': 55, 'twenty-seven': 27, 'seventy-four': 74, 'thirty-seven': 37, 'twenty-six': 26, 'sixty-six': 66, 'eighty-four': 84, 'sixty-four': 64, 'forty-eight': 48, 'fifty-four': 54, 'eighty-one': 81, 'thirty-three': 33, 'forty-four': 44, 'fifty-nine': 59, 'thirty-eight': 38, 'forty-six': 46, 'sixty-nine': 69, 'sixty-one': 61, 'sixty-three': 63, 'ninety-eight': 98, 'seventy-six': 76, 'seventy-one': 71, 'ninety-three': 93, 'fifty-three': 53, 'fifty-six': 56, 'seventy-five': 75, 'eighty-seven': 87, 'ninety-seven': 97, 'ninety-six': 96, 'ninety-nine': 99, 'twenty-one': 21, 'twenty-five': 25, 'ninety-five': 95, 'thirty-nine': 39, 'sixty-eight': 68, 'thirty-six': 36, 'twenty-four': 24, 'seventy-three': 73, 'seventy-two': 72, 'ninety-two': 92, 'twenty-three': 23, 'twenty-two': 22, 'forty-nine': 49, 'sixty-five': 65, 'fifty-one': 51, 'forty-five': 45}
powers = {'vigintitrillion': 1000000000000000000000000000000000000000000000000000000000000000000000000, 'septillion': 1000000000000000000000000, 'nonillion': 1000000000000000000000000000000, 'tredecillion': 1000000000000000000000000000000000000000000, 'vigintiquadrillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000, 'decillion': 1000000000000000000000000000000000, 'billion': 1000000000, 'duovigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000, 'thousand': 1000, 'duodecillion': 1000000000000000000000000000000000000000, 'septemdecillion': 1000000000000000000000000000000000000000000000000000000, 'vigintinonillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'octillion': 1000000000000000000000000000, 'quinvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000, 'octodecillion': 1000000000000000000000000000000000000000000000000000000000, 'novemdecillion': 1000000000000000000000000000000000000000000000000000000000000, 'trigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'quindecillion': 1000000000000000000000000000000000000000000000000, 'duotrigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'quattuordecillion': 1000000000000000000000000000000000000000000000, 'quadrillion': 1000000000000000, 'vigintiseptillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'vigintillion': 1000000000000000000000000000000000000000000000000000000000000000, 'untrigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'centillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'undecillion': 1000000000000000000000000000000000000, 'vigintunillion': 1000000000000000000000000000000000000000000000000000000000000000000, 'million': 1000000, 'septvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'vigintisextillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'vigintiduoillion': 1000000000000000000000000000000000000000000000000000000000000000000000, 'sextillion': 1000000000000000000000, 'octovigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'nonvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'sexdecillion': 1000000000000000000000000000000000000000000000000000, 'vigintoctillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'sexvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'trevigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000, 'unvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000, 'hundred': 100, 'quattuorvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000, 'quintillion': 1000000000000000000, 'googol': 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'vigintiquintrillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000}

def parse_int(string):
    result=0
    a=string.split(" ")
    b=[]
    
    for c in a:
        if c in numbers:
            b.append(c)
        elif c in powers:
            b[-1]+=" "+c
        elif c=="and":
            continue
        else:
            print("ERROR: UNRECOGNISED WORD(S).")
    
    for d, e in enumerate(b):
        if len(e.split(" "))==1:
            b[d]=numbers[e]
        else:
            b[d]=e.split(" ")
            b[d][0]=numbers[b[d][0]]
            f=1
            while f<len(b[d]):
                b[d][f]=powers[b[d][f]]
                f+=1
    
    if not(isinstance(b[0],int)):
           while len(b[0])>2:
               b[0][1]*=b[0][2]
               b[0].pop(2)
    
    while len(b)>0:
        if len(b)==1:
            if isinstance(b[0],int):
                result+=b[0]
                b.pop(0)
            else:
                if result==0:
                    result=1
                while len(b[0])>2:
                    b[0][1]*=b[0][2]
                    b[0].pop(2)
                result+=b[0][0]
                b.pop(0)
        else:
            if isinstance(b[1],int):
                b[1]+=b[0][0]*b[0][1]
                b.pop(0)
            else:
                while len(b[1])>2:
                    b[1][1]*=b[1][2]
                    b[1].pop(2)
                
                if b[0][1]<b[1][1]:
                    b[1][0]+=b[0][0]*b[0][1]
                    b.pop(0)
                else:
                    result+=b[0][0]*b[0][1]
                    b.pop(0)
    
    return(result)

The Output

Currently, the function returns the wrong results for 3 for "two thousand", 11 for "ten thousand", and 500003 for "five hundred thousand three hundred". It would be helpful if it returned the right integer. I will update frequently.

[How to debug small programs.](//ericlippert.com/2014/03/05/how-to-debug-small-programs/) | [What is a debugger and how can it help me diagnose problems?](//stackoverflow.com/q/25385173/843953) Step through your code and narrow down the problem into a [mre]. Then ask a specific question. _"Why is my code doing this"_ is [too broad for Stack Overflow.](//meta.stackoverflow.com/a/253788/843953) Please also take the [tour], read [ask] and [what's on-topic](/help/on-topic). Welcome to Stack Overflow! — Pranav Hosangadi, Dec 01 '20 at 17:52
Why are you rejoining the string with `string=" ".join(string)`? A list of words is way easier to manipulate than a long text not broken into words! — Stef, Dec 02 '20 at 11:08
The simplest way to write a recursive function is to somehow identify the relation `parse_int("nine hundred and ninety-nine thousand nine hundred and ninety-nine") == parse_int("nine hundred and ninety-nine") * numbers["thousand"] + parse_int("nine hundred and ninety-nine")` — Stef, Dec 02 '20 at 11:14
I suggest splitting the string into words using `words = string.replace('and', ' ').replace('-', ' ').split()`, then turning it into a list of numbers using `number_list = map(numbers.get, words)` or `number_list = [numbers[w] for w in words]` then somehow cutting this list of numbers into three parts `first_half`, `multiplier`, and `second_half`, where `multiplier` is a single-number which is in your dictionary (`1000` in my previous comment), then applying the function recursively to `first_half` and `second_half`. — Stef, Dec 02 '20 at 11:19
You need to recognise which word is the multiplier. What is so special about `"thousand"` in `"nine hundred and ninety-nine thousand nine hundred and ninety-nine"`? Why did we choose `"thousand"` and not `"hundred"` or `"ninety"` or `"nine"`? — Stef, Dec 02 '20 at 11:21
Thanks, I switched to iterative because it is hard to find errors in recursive functions, but it is now fixed. [The solution](https://www.codewars.com/kata/reviews/5b407792494dc47cf00007cc/groups/5fc7c228c8999f00011ee5c3) may not be pretty, but it works. — niamulbengali, Dec 02 '20 at 16:47

score 1 · Accepted Answer · answered Dec 02 '20 at 16:45

Through trial and error, I finished working on the parse_int() function, so here is the result.

def parse_int(string):
    numbers = {'zero':0,'one':1,'two':2,'three':3,'four':4,'five':5,'six':6,'seven':7,'eight':8,'nine':9,'ten':10,'eleven':11,'twelve':12,'thirteen':13,'fourteen':14,'fifteen':15,'sixteen':16,'seventeen':17,'eighteen':18,'nineteen':19,'twenty':20,'thirty':30,'forty':40,'fifty':50,'sixty':60,'seventy':70,'eighty':80,'ninety':90,'eighty-six': 86, 'thirty-one': 31, 'forty-three': 43, 'forty-two': 42, 'fifty-eight': 58, 'sixty-seven': 67, 'thirty-two': 32, 'thirty-five': 35, 'seventy-nine': 79, 'thirty-four': 34, 'fifty-seven': 57, 'twenty-nine': 29, 'eighty-nine': 89, 'ninety-four': 94, 'seventy-eight': 78, 'ninety-one': 91, 'forty-one': 41, 'sixty-two': 62, 'twenty-eight': 28, 'eighty-eight': 88, 'seventy-seven': 77, 'forty-seven': 47, 'eighty-five': 85, 'eighty-three': 83, 'fifty-two': 52, 'eighty-two': 82, 'fifty-five': 55, 'twenty-seven': 27, 'seventy-four': 74, 'thirty-seven': 37, 'twenty-six': 26, 'sixty-six': 66, 'eighty-four': 84, 'sixty-four': 64, 'forty-eight': 48, 'fifty-four': 54, 'eighty-one': 81, 'thirty-three': 33, 'forty-four': 44, 'fifty-nine': 59, 'thirty-eight': 38, 'forty-six': 46, 'sixty-nine': 69, 'sixty-one': 61, 'sixty-three': 63, 'ninety-eight': 98, 'seventy-six': 76, 'seventy-one': 71, 'ninety-three': 93, 'fifty-three': 53, 'fifty-six': 56, 'seventy-five': 75, 'eighty-seven': 87, 'ninety-seven': 97, 'ninety-six': 96, 'ninety-nine': 99, 'twenty-one': 21, 'twenty-five': 25, 'ninety-five': 95, 'thirty-nine': 39, 'sixty-eight': 68, 'thirty-six': 36, 'twenty-four': 24, 'seventy-three': 73, 'seventy-two': 72, 'ninety-two': 92, 'twenty-three': 23, 'twenty-two': 22, 'forty-nine': 49, 'sixty-five': 65, 'fifty-one': 51, 'forty-five': 45}
    powers = {'vigintitrillion': 1000000000000000000000000000000000000000000000000000000000000000000000000, 'septillion': 1000000000000000000000000, 'nonillion': 1000000000000000000000000000000, 'tredecillion': 1000000000000000000000000000000000000000000, 'vigintiquadrillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000, 'decillion': 1000000000000000000000000000000000, 'billion': 1000000000, 'duovigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000, 'thousand': 1000, 'duodecillion': 1000000000000000000000000000000000000000, 'septemdecillion': 1000000000000000000000000000000000000000000000000000000, 'vigintinonillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'octillion': 1000000000000000000000000000, 'quinvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000, 'octodecillion': 1000000000000000000000000000000000000000000000000000000000, 'novemdecillion': 1000000000000000000000000000000000000000000000000000000000000, 'trigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'quindecillion': 1000000000000000000000000000000000000000000000000, 'duotrigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'quattuordecillion': 1000000000000000000000000000000000000000000000, 'quadrillion': 1000000000000000, 'vigintiseptillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'vigintillion': 1000000000000000000000000000000000000000000000000000000000000000, 'untrigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'centillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'undecillion': 1000000000000000000000000000000000000, 'vigintunillion': 1000000000000000000000000000000000000000000000000000000000000000000, 'million': 1000000, 'septvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'vigintisextillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'vigintiduoillion': 1000000000000000000000000000000000000000000000000000000000000000000000, 'sextillion': 1000000000000000000000, 'octovigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'nonvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'sexdecillion': 1000000000000000000000000000000000000000000000000000, 'vigintoctillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'sexvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'trevigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000, 'unvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000, 'hundred': 100, 'quattuorvigintillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000, 'quintillion': 1000000000000000000, 'googol': 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000, 'vigintiquintrillion': 1000000000000000000000000000000000000000000000000000000000000000000000000000000}
    
    result=0
    a=string.split(" ")
    b=[]
    
    for c in a:
        if c in numbers:
            b.append(c)
        elif c in powers:
            b[-1]+=" "+c
        elif c=="and":
            continue
        else:
            print("ERROR: UNRECOGNISED WORD(S).")
            return(None)
    
    for d, e in enumerate(b):
        if len(e.split(" "))==1:
            b[d]=numbers[e]
        else:
            b[d]=e.split(" ")
            b[d][0]=numbers[b[d][0]]
            f=1
            while f<len(b[d]):
                b[d][f]=powers[b[d][f]]
                f+=1
    
    if not(isinstance(b[0],int)):
           while len(b[0])>2:
               b[0][1]*=b[0][2]
               b[0].pop(2)
    
    while len(b)>0:
        if len(b)==1:
            if isinstance(b[0],int):
                result+=b[0]
                b.pop(0)
            else:
                while len(b[0])>1:
                    b[0][0]*=b[0][1]
                    b[0].pop(1)
                result+=b[0][0]
                b.pop(0)
        else:
            if isinstance(b[1],int):
                b[1]+=b[0][0]*b[0][1]
                b.pop(0)
            else:
                while len(b[1])>2:
                    b[1][1]*=b[1][2]
                    b[1].pop(2)
                
                if b[0][1]<b[1][1]:
                    b[1][0]+=b[0][0]*b[0][1]
                    b.pop(0)
                else:
                    result+=b[0][0]*b[0][1]
                    b.pop(0)
    
    return(result)

English numerals to integers (iterative function)

Background

The Issue

The Code

The Output

1 Answers1