Codeforces Round 408 (Div. 2)
B
Find The Bone
Codeforces
1300
原题
← AC →
翻译中…

Zane the wizard is going to perform a magic show shuffling the cups.

翻译中…

There are $*n*$ cups, numbered from $1$ to $*n*$, placed along the $*x*$-axis on a table that has $*m*$ holes on it. More precisely, cup $*i*$ is on the table at the position $*x* = *i*$.

翻译中…

The problematic bone is initially at the position $*x* = 1$. Zane will confuse the audience by swapping the cups $*k*$ times, the $*i*$-th time of which involves the cups at the positions $*x* = *u*_{*i*}$ and $*x* = *v*_{*i*}$. If the bone happens to be at the position where there is a hole at any time, it will fall into the hole onto the ground and will not be affected by future swapping operations.

翻译中…

Do not forget that Zane is a wizard. When he swaps the cups, he does not move them ordinarily. Instead, he teleports the cups (along with the bone, if it is inside) to the intended positions. Therefore, for example, when he swaps the cup at $*x* = 4$ and the one at $*x* = 6$, they will not be at the position $*x* = 5$ at any moment during the operation.

翻译中…

image

翻译中…

Zane’s puppy, Inzane, is in trouble. Zane is away on his vacation, and Inzane cannot find his beloved bone, as it would be too exhausting to try opening all the cups. Inzane knows that the Codeforces community has successfully helped Zane, so he wants to see if it could help him solve his problem too. Help Inzane determine the final position of the bone.

翻译中…

Input

翻译中…

The first line contains three integers $*n*$, $*m*$, and $*k*$ ($2 ≤ *n* ≤ 10^{6}$, $1 ≤ *m* ≤ *n*$, $1 ≤ *k* ≤ 3·10^{5}$) — the number of cups, the number of holes on the table, and the number of swapping operations, respectively.

翻译中…

The second line contains $*m*$ distinct integers $*h*_{1}, *h*_{2}, ..., *h*_{*m*}$ ($1 ≤ *h*_{*i*} ≤ *n*$) — the positions along the $*x*$-axis where there is a hole on the table.

翻译中…

Each of the next $*k*$ lines contains two integers $*u*_{*i*}$ and $*v*_{*i*}$ ($1 ≤ *u*_{*i*}, *v*_{*i*} ≤ *n*$, $*u*_{*i*} ≠ *v*_{*i*}$) — the positions of the cups to be swapped.

翻译中…

Output

翻译中…

Print one integer — the final position along the $*x*$-axis of the bone.

翻译中…

Note

翻译中…

In the first sample, after the operations, the bone becomes at $*x* = 2$, $*x* = 5$, $*x* = 7$, and $*x* = 1$, respectively.

翻译中…

In the second sample, after the first operation, the bone becomes at $*x* = 2$, and falls into the hole onto the ground.

翻译中…

样例

Input #1
7 3 4
3 4 6
1 2
2 5
5 7
7 1
Output #1
1
InputCopy OutputCopy
Input #2
5 1 2
2
1 2
2 4
Output #2
2
InputCopy OutputCopy
题目信息
题号
796B
时间限制
2 s
内存限制
256 MB
标签
模拟

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。