| 123456789101112131415161718192021 |
- class Preg():
- def __init__(self):
- self.preg=[]
- self.cur_preg=0
- def add(self,val):
- self.preg.append(val)
- def clean(self):
- self.preg=[]
- def cur(self):
- return self.preg[self.cur_preg]
- def prev(self):
- self.cur_preg=max(self.cur_preg-1, 0)
- return self.preg[self.cur_preg]
- def next(self):
- self.cur_preg=min(self.cur_preg+1, len(self.preg)-1)
- return self.preg[self.cur_preg]
|
