Problem Statement

There are N sequences of integers.
The $i-th (1 \leq i \leq N) sequence has L_i$ terms; the $j-th (1 \leq j \leq L_i)$ term of the i-th sequence is a_{i, j}.
You are given Q queries. For the $k-th (1 \leq k \leq Q)$ query, given integers s_k and t_k, find the t_k-th term of the s_k-th sequence.

Input

The input is given from Standard Input in the following format:
N Q
$L_1 a_{1, 1} \ldots a_{1, L_1}$
$\vdots$
$L_N a_{N, 1} \ldots a_{N, L_N}$
s_1 t_1
$\vdots$
s_Q t_Q

Output

Print Q lines. The $k-th (1 \leq k \leq Q)$ line should contain the answer to the k-th query.

Constraints

• $1 \leq N, Q \leq 2 \times 10^5$
• $L_i \geq 1$ $, (1 \leq i \leq N)$
• $\sum_{i=1}^N L_i \leq 2 \times 10^5$
• $1 \leq a_{i, j} \leq 10^9$ $, (1 \leq i \leq N, 1 \leq j \leq L_i)$
• $1 \leq s_k \leq N, 1 \leq t_k \leq L_{s_k}$ $, (1 \leq k \leq Q)$
• All values in the input are integers.

Sample Input 1

2 2
3 1 4 7
2 5 9
1 3
2 1

Sample Output 1

7
5

The 1-st sequence is (1, 4, 7) and the 2-nd is (5, 9).
The answer to each query is as follows:

• The 3-rd term of the 1-st sequence is 7.
• The 1-st term of the 2-nd sequence is 5.

Sample Input 2

3 4
4 128 741 239 901
2 1 1
3 314 159 26535
1 1
2 2
3 3
1 4

Sample Output 2

128
1
26535
901

见题面 Input 部分

见题面 Output 部分