Use itertools.cycle to repeat over balloons

If branches have the same balloons, then `cycle` will cause the list to be repeated
once per branch.

However, if branches have different balloons, then assuming that all the balloon values for
all branches are listed, the list will be iterated over normally.

This

src/tja2fumen/converters.py

@@ -209,7 +209,6 @@ def convert_tja_to_fumen(tja: TJACourse) -> FumenCourse:
         current_levelhold = False
         branch_types: List[str] = []
         branch_conditions: List[Tuple[float, float]] = []
-        course_balloons = tja.balloon.copy()
 
         # Iterate over pairs of TJA and Fumen measures
         for idx_m, (measure_tja, measure_fumen) in \
@@ -334,7 +333,7 @@ def convert_tja_to_fumen(tja: TJACourse) -> FumenCourse:
                     current_drumroll = note
                 elif note.note_type in ["Balloon", "Kusudama"]:
                     try:
-                        note.hits = course_balloons.pop(0)
+                        note.hits = next(tja.balloon)
                     except IndexError:
                         warnings.warn(f"Not enough values for 'BALLOON:' "
                                       f"({tja.balloon}). Using value=1 to "

src/tja2fumen/parsers.py

@@ -8,6 +8,7 @@ import struct
 import warnings
 from copy import deepcopy
 from typing import BinaryIO, Any, List, Dict, Tuple
+from itertools import cycle
 
 from tja2fumen.classes import (TJASong, TJACourse, TJAMeasure, TJAData,
                                FumenCourse, FumenMeasure, FumenBranch,
@@ -121,7 +122,7 @@ def split_tja_lines_into_courses(lines: List[str]) -> TJASong:
             elif name_upper == 'BALLOON':
                 if value:
                     balloons = [int(v) for v in value.split(",") if v]
-                    parsed_tja.courses[current_course].balloon = balloons
+                    parsed_tja.courses[current_course].balloon = cycle(balloons)
             elif name_upper == 'STYLE':
                 # Reset the course name to remove "P1/P2" that may have been
                 # added by a previous STYLE:DOUBLE chart