Codeforces Global Round 14
D
Phoenix and Socks
Codeforces
1500
原题
← CE →
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To satisfy his love of matching socks, Phoenix has brought his $n$ socks ($n$ is even) to the sock store. Each of his socks has a color $c_i$ and is either a left sock or right sock.

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Phoenix can pay one dollar to the sock store to either:

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  • recolor a sock to any color $c'$ $(1 \le c' \le n)$
  • turn a left sock into a right sock
  • turn a right sock into a left sock
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The sock store may perform each of these changes any number of times. Note that the color of a left sock doesn't change when it turns into a right sock, and vice versa.

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A matching pair of socks is a left and right sock with the same color. What is the minimum cost for Phoenix to make $n/2$ matching pairs? Each sock must be included in exactly one matching pair.

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Input

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The input consists of multiple test cases. The first line contains an integer $t$ ($1 \le t \le 1000$) — the number of test cases.

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The first line of each test case contains three integers $n$, $l$, and $r$ ($2 \le n \le 2 \cdot 10^5$; $n$ is even; $0 \le l, r \le n$; $l+r=n$) — the total number of socks, and the number of left and right socks, respectively.

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The next line contains $n$ integers $c_i$ ($1 \le c_i \le n$) — the colors of the socks. The first $l$ socks are left socks, while the next $r$ socks are right socks.

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It is guaranteed that the sum of $n$ across all the test cases will not exceed $2 \cdot 10^5$.

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Output

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For each test case, print one integer — the minimum cost for Phoenix to make $n/2$ matching pairs. Each sock must be included in exactly one matching pair.

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Note

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In the first test case, Phoenix can pay $2$ dollars to:

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  • recolor sock $1$ to color $2$
  • recolor sock $3$ to color $2$
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There are now $3$ matching pairs. For example, pairs $(1, 4)$, $(2, 5)$, and $(3, 6)$ are matching.

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In the second test case, Phoenix can pay $3$ dollars to:

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  • turn sock $6$ from a right sock to a left sock
  • recolor sock $3$ to color $1$
  • recolor sock $4$ to color $1$
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There are now $3$ matching pairs. For example, pairs $(1, 3)$, $(2, 4)$, and $(5, 6)$ are matching.

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样例

Input #1
4
6 3 3
1 2 3 2 2 2
6 2 4
1 1 2 2 2 2
6 5 1
6 5 4 3 2 1
4 0 4
4 4 4 3
Output #1
2
3
5
3
InputCopy OutputCopy
题目信息
题号
1515D
时间限制
2 s
内存限制
256 MB
标签
贪心
排序
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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。