65 lines
1.8 KiB
Python
65 lines
1.8 KiB
Python
from typing import Optional
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#
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# 1) Insertion, deletion and random access of array
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# 2) Assumes int for element type
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#
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# Author: Wenru
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#
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class MyArray:
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"""A simple wrapper around List.
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You cannot have -1 in the array.
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"""
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def __init__(self, capacity: int):
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self._data = []
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self._count = 0
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self._capacity = capacity
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def __getitem__(self, position: int) -> int:
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"""Support for subscript.
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Perhaps better than the find() method below.
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"""
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return self._data[position]
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def find(self, index: int) -> Optional[int]:
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if index >= self._count or index <= -self._count: return None
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return self._data[index]
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def delete(self, index: int) -> bool:
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if index >= self._count or index <= -self._count: return False
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self._data[index:-1] = self._data[index+1:]
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self._count -= 1
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return True
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def insert(self, index: int, value: int) -> bool:
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if index >= self._count or index <= -self._count: return False
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if self._capacity == self._count: return False
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self._data.insert(index, value)
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self._count += 1
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return True
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def insert_to_tail(self, value: int) -> bool:
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if self._count == self._capacity: return False
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if self._count == len(self._data):
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self._data.append(value)
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else:
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self._data[self._count] = value
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self._count += 1
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return True
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def __repr__(self) -> str:
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return " ".join(str(num) for num in self._data[:self._count])
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def print_all(self):
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for num in self._data[:self._count]:
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print(f"{num}", end=" ")
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print("\n", flush=True)
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if __name__ == "__main__":
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a = MyArray(6)
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for i in range(6):
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a.insert_to_tail(i)
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a.delete(2)
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print(a)
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a.insert_to_tail(7)
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print(a) |