import re

SHOW_INTERMEDIARY_STATE = True

def remove_whitespace(s):
    return re.sub(r"\s", "", s)

def parse_source(source):
    ops = []
    for line in source.split("\n"):
        line = remove_whitespace(line)
        if not line:
            continue
        assert line.count("=") == 1
        l,_,r = line.partition("=")
        ops.append((l, r))
    return ops

def exec(program_or_source, s):
    if isinstance(program_or_source, list):
        program = program_or_source
    else:
        program = parse_source(program_or_source)

    pc = 0

    if SHOW_INTERMEDIARY_STATE:
        print(pc, s)
    while pc < len(program):
        l,r = program[pc]
        if l in s:
            s = s.replace(l, r, 1)
            if SHOW_INTERMEDIARY_STATE:
                print(pc, s)
            pc = 0
        else:
            pc += 1
    return s

#given a string containing only X, a, b, and c, move all "X"es to the end of the string.
source="""
0<INCREMENT> = 1
1<INCREMENT> = 2
2<INCREMENT> = 3
3<INCREMENT> = 4
4<INCREMENT> = 5
5<INCREMENT> = 6
6<INCREMENT> = 7
7<INCREMENT> = 8
8<INCREMENT> = 9
9<INCREMENT> = <INCREMENT>0
<INCREMENT> = 1

0<DECREMENT> = <DECREMENT>9
1<DECREMENT> = 0
2<DECREMENT> = 1
3<DECREMENT> = 2
4<DECREMENT> = 3
5<DECREMENT> = 4
6<DECREMENT> = 5
7<DECREMENT> = 6
8<DECREMENT> = 7
9<DECREMENT> = 8


<TRAVEL_RIGHT_THEN_DECREMENT>0 = 0<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>1 = 1<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>2 = 2<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>3 = 3<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>4 = 4<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>5 = 5<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>6 = 6<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>7 = 7<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>8 = 8<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT>9 = 9<TRAVEL_RIGHT_THEN_DECREMENT>
<TRAVEL_RIGHT_THEN_DECREMENT> = <DECREMENT>

<TRIM_LEADING_ZEROES>00 = <TRIM_LEADING_ZEROES>0
<TRIM_LEADING_ZEROES>01= 1
<TRIM_LEADING_ZEROES>02= 2
<TRIM_LEADING_ZEROES>03= 3
<TRIM_LEADING_ZEROES>04= 4
<TRIM_LEADING_ZEROES>05= 5
<TRIM_LEADING_ZEROES>06= 6
<TRIM_LEADING_ZEROES>07= 7
<TRIM_LEADING_ZEROES>08= 8
<TRIM_LEADING_ZEROES>09= 9
<TRIM_LEADING_ZEROES>=

+=<INFIX_ADD>
<INFIX_ADD>0=
<INFIX_ADD>=<INCREMENT><INFIX_ADD><TRIM_LEADING_ZEROES><TRAVEL_RIGHT_THEN_DECREMENT>
"""

import random
s = "123+119+8"
print(exec(source, s)) # 250