day18

part1.py

from enum import Enum
import sys


class State(Enum):
    DEFAULT = -1
    NUMBER = 1
    PARENTHESIS = 2
    OPERATOR = 3


class Operator(Enum):
    MULT = 1
    ADD = 2


class Number:
    def __init__(self, val):
        self.value = val

    def __str__(self):
        return 'NUM: %d' % (self.value)


class PAREN(Enum):
    OPEN = 1
    CLOSE = 2


def tokenize(S):
    R = []
    state = State.DEFAULT
    par_state = 0
    numbuf = ['']
    for i, k in enumerate(S):
        if k in '0123456789':
            if state != State.NUMBER:
                numbuf = [k]
                state = State.NUMBER
            else:
                numbuf.append(k)
            continue
        else:
            # closure of number
            if state == State.NUMBER:
                val = int(''.join(numbuf))
                R.append(Number(val))
                numbuf = ['']

        if k in '()':
            state = State.PARENTHESIS
            if k == '(':
                R.append(PAREN.OPEN)
                par_state += 1
            if k == ')':
                R.append(PAREN.CLOSE)
                par_state -= 1
            assert (par_state >= 0)
            continue
        if k == '+':
            R.append(Operator.ADD)
            continue
        if k == '*':
            R.append(Operator.MULT)
            continue

        if k == ' ':
            state = State.DEFAULT
            continue

        raise Exception('oops', k)
    if state == State.NUMBER:
        val = int(''.join(numbuf))
        R.append(Number(val))
    return R


def proc(listTokens):
    #print("PROCESSING")
    #for ll in listTokens:
    #    print(ll)
    #print('END')
    R = []
    i = 0

    # process parenthesis blocks replacing them
    while True:
        if i == len(listTokens):
            break
        if listTokens[i] == PAREN.OPEN:
            # print('opening')
            state = 1
            for i1 in range(i + 1, len(listTokens)):
                if listTokens[i1] == PAREN.OPEN:
                    state += 1
                if listTokens[i1] == PAREN.CLOSE:
                    state -= 1
                if state == 0:
                    R.append(Number(proc(listTokens[i + 1:i1])))
                    break
            i = i1 + 1
            continue
        if listTokens[i] == PAREN.CLOSE:
            # print(listTokens, i)
            raise Exception('oops2')
        R.append(listTokens[i])
        i += 1
    val = R[0].value
    lastop = None
    for v in R[1:]:
        if lastop is None and isinstance(v, Operator):
            lastop = v
            continue
        if lastop is not None and isinstance(v, Number):
            if lastop == Operator.MULT:
                val = val * v.value
            if lastop == Operator.ADD:
                val = val + v.value
            lastop = None
    return val


def doall(fname):
    for ll in open(fname, 'r').read().split('\n'):
        print(proc(tokenize(ll)))


if __name__ == '__main__':
    S = sys.argv[1]  # '1 + 2 * 3 + 4 * 5 + 6'
    T = tokenize(S)
    print(S)
    print('TOKENS')
    for a in T:
        print(a)
    print('----')
    print(T)
    R = proc(T)
    print('RESULT')
    print(R)

part2.py

from enum import Enum
import copy
import sys


class State(Enum):
    DEFAULT = -1
    NUMBER = 1
    PARENTHESIS = 2
    OPERATOR = 3


class Operator(Enum):
    MULT = 1
    ADD = 2


class Number:
    def __init__(self, val):
        self.value = val

    def __str__(self):
        return 'NUM: %d' % (self.value)


class PAREN(Enum):
    OPEN = 1
    CLOSE = 2


def tokenize(S):
    R = []
    state = State.DEFAULT
    par_state = 0
    numbuf = ['']
    for i, k in enumerate(S):
        if k in '0123456789':
            if state != State.NUMBER:
                numbuf = [k]
                state = State.NUMBER
            else:
                numbuf.append(k)
            continue
        else:
            # closure of number
            if state == State.NUMBER:
                val = int(''.join(numbuf))
                R.append(Number(val))
                numbuf = ['']

        if k in '()':
            state = State.PARENTHESIS
            if k == '(':
                R.append(PAREN.OPEN)
                par_state += 1
            if k == ')':
                R.append(PAREN.CLOSE)
                par_state -= 1
            assert (par_state >= 0)
            continue
        if k == '+':
            R.append(Operator.ADD)
            continue
        if k == '*':
            R.append(Operator.MULT)
            continue

        if k == ' ':
            state = State.DEFAULT
            continue

        raise Exception('oops', k)
    if state == State.NUMBER:
        val = int(''.join(numbuf))
        R.append(Number(val))
    return R


def proc(listTokens):
    R = []
    i = 0

    # process parenthesis blocks replacing them
    while True:
        if i == len(listTokens):
            break
        if listTokens[i] == PAREN.OPEN:
            # print('opening')
            state = 1
            for i1 in range(i + 1, len(listTokens)):
                if listTokens[i1] == PAREN.OPEN:
                    state += 1
                if listTokens[i1] == PAREN.CLOSE:
                    state -= 1
                if state == 0:
                    R.append(Number(proc(listTokens[i + 1:i1])))
                    break
            i = i1 + 1
            continue
        if listTokens[i] == PAREN.CLOSE:
            # print(listTokens, i)
            raise Exception('oops2')
        R.append(listTokens[i])
        i += 1
    R1 = copy.copy(R)
    for curop in [Operator.ADD, Operator.MULT]:
        lastval = R1[0]
        accum = False
        R2 = []
        #print(" PROCESSING")
        #for ll in R1:
        #    print(ll)
        #print('END')

        for v in R1[1:]:
            if isinstance(v, Operator):
                if v == curop:
                    accum = True
                else:
                    accum = False
                    R2.append(lastval)
                    R2.append(v)
            if isinstance(v, Number):
                if accum:
                    if curop == Operator.MULT:
                        val = lastval.value * v.value
                    if curop == Operator.ADD:
                        val = lastval.value + v.value
                    lastval = Number(val)
                else:
                    lastval = v
        R2.append(lastval)
        R1 = R2
    ret = R2[0].value
    #print('RESULT', ret)
    return ret


def doall(fname):
    for ll in open(fname, 'r').read().split('\n'):
        print(proc(tokenize(ll)))


if __name__ == '__main__':
    S = sys.argv[1]  # '1 + 2 * 3 + 4 * 5 + 6'
    T = tokenize(S)
    print(S)
    print('TOKENS')
    for a in T:
        print(a)
    print('----')
    print(T)
    R = proc(T)
    print('RESULT')
    print(R)