1
1
12345
0123456789
8
78




0123456789
2
1
word[-100] = 
word[-7] = 
word[-6] = 
word[-5] = H
word[-4] = e
word[-3] = l
word[-2] = p
word[-1] = A
word[0] = H
word[1] = e
word[2] = l
word[3] = p
word[4] = A
word[5] = 
word[6] = 
word[7] = 
word[100] = 

A
1234
123
12
1






B





C

0123

01
012345

D


4


45

E

01234

01
012345

F

234


23
2345

F