| Time Limit | $1$ 秒/Second(s) | Memory Limit | $512$ 兆字节/Megabyte(s) |
| 提交总数 | $1367$ | 正确数量 | $814$ | "
| 裁判形式 | 标准裁判/Standard Judge | 我的状态 | 尚未尝试 |
| 难度 | 分类标签 | STL |
Vector
For a dynamic array A={a0,a1,...}
A={a0,a1,...} of integers, perform a sequence of the following operations:
0 pushBack(x): add element x at the end of A randomAccess(p):
1 p print element a[p]
2 popBack(): delete the last element of A
A is a 0-origin array and it is empty in the initial state.
The input is given in the following format.
q
q1
q2
...
qyi
Each query queryi is given by
0 x
or
1 p
or
2
where the first digits 0, 1 and 2 represent pushBack, randomAccess and popBack operations respectively.
randomAccess and popBack operations will not be given for an empty array.
1≤q≤200,000
0≤p< the size of A
−1,000,000,000≤x≤1,000,000,000
8
0 1
0 2
0 3
2
0 4
1 0
1 1
1 2
1
2
4