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A15913 | Trust Nobody

时间限制1s
内存限制256MB
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题目描述

There is a group of $n$ people. Some of them might be liars, who always tell lies. Other people always tell the truth. The $i$ -th person says "There are at least $l_i$ liars amongst us". Determine if what people are saying is contradictory, or if it is possible. If it is possible, output the number of liars in the group. If there are multiple possible answers, output any one of them.

输入格式

The first line contains a single integer $t$ ( $1 \leq t \leq 1000$ ) — the number of test cases.

The first line of each test case contains a single integer $n$ ( $1 \leq n \leq 100$ ).

The second line of each test case contains $n$ integers $l_i$ ( $0 \leq l_i \leq n$ ) — the number said by the $i$ -th person.

It's guaranteed that the sum of all $n$ does not exceed $10^4$ .

输出格式

For each test case output a single integer. If what people are saying is contradictory, output $-1$ . Otherwise, output the number of liars in the group. If there are multiple possible answers, output any one of them.

输入输出样例

输入 #1
7
2
1 2
2
2 2
2
0 0
1
1
1
0
5
5 5 3 3 5
6
5 3 6 6 3 5
输出 #1
1
-1
0
-1
0
3
4
C++ 编辑器
输入
输出