• <ins id="pjuwb"></ins>
    <blockquote id="pjuwb"><pre id="pjuwb"></pre></blockquote>
    <noscript id="pjuwb"></noscript>
          <sup id="pjuwb"><pre id="pjuwb"></pre></sup>
            <dd id="pjuwb"></dd>
            <abbr id="pjuwb"></abbr>
            posts - 74,  comments - 33,  trackbacks - 0
            Perfect Service
            Time Limit: 2000MS Memory Limit: 65536K
            Total Submissions: 661 Accepted: 319

            Description

            A network is composed of N computers connected by N ? 1 communication links such that any two computers can be communicated via a unique route. Two computers are said to be adjacent if there is a communication link between them. The neighbors of a computer is the set of computers which are adjacent to it. In order to quickly access and retrieve large amounts of information, we need to select some computers acting as servers to provide resources to their neighbors. Note that a server can serve all its neighbors. A set of servers in the network forms a perfect service if every client (non-server) is served by exactly one server. The problem is to find a minimum number of servers which forms a perfect service, and we call this number perfect service number.

            We assume that N (≤ 10000) is a positive integer and these N computers are numbered from 1 to N. For example, Figure 1 illustrates a network comprised of six computers, where black nodes represent servers and white nodes represent clients. In Figure 1(a), servers 3 and 5 do not form a perfect service because client 4 is adjacent to both servers 3 and 5 and thus it is served by two servers which contradicts the assumption. Conversely, servers 3 and 4 form a perfect service as shown in Figure 1(b). This set also has the minimum cardinality. Therefore, the perfect service number of this example equals two.

            Your task is to write a program to compute the perfect service number.

            Input

            The input consists of a number of test cases. The format of each test case is as follows: The first line contains one positive integer, N, which represents the number of computers in the network. The next N ? 1 lines contain all of the communication links and one line for each link. Each line is represented by two positive integers separated by a single space. Finally, a 0 at the (N + 1)th line indicates the end of the first test case.

            The next test case starts after the previous ending symbol 0. A ?1 indicates the end of the whole inputs.

            Output

            The output contains one line for each test case. Each line contains a positive integer, which is
            the perfect service number.

            Sample Input

            6
            1 3
            2 3
            3 4
            4 5
            4 6
            0
            2
            1 2
            -1

            Sample Output

            2
            1
            樹的最小支配集:和3659一樣。TreeDP求解:
            代碼同上篇隨筆一樣:
            posted on 2009-04-09 22:58 KNIGHT 閱讀(119) 評論(0)  編輯 收藏 引用
            <2009年4月>
            2930311234
            567891011
            12131415161718
            19202122232425
            262728293012
            3456789

            常用鏈接

            留言簿(8)

            隨筆檔案

            文章檔案

            Friends

            OJ

            搜索

            •  

            最新評論

            閱讀排行榜

            評論排行榜

            久久精品国产亚洲av麻豆色欲| 国内精品久久久久久久久 | 漂亮人妻被黑人久久精品| 久久国产色AV免费看| 亚洲国产成人久久综合碰碰动漫3d| 无夜精品久久久久久| 久久r热这里有精品视频| 无码人妻久久一区二区三区蜜桃 | 免费观看成人久久网免费观看| 亚洲精品成人网久久久久久| 国产成人精品久久一区二区三区av | 亚洲午夜久久久影院| 久久精品国产一区二区三区| 久久亚洲国产中v天仙www| 免费精品国产日韩热久久| 久久免费香蕉视频| 久久一区二区三区99| 91久久婷婷国产综合精品青草| 无码久久精品国产亚洲Av影片| 久久精品免费一区二区| 久久精品亚洲AV久久久无码 | 久久无码AV中文出轨人妻| 久久精品一区二区国产| 人妻精品久久久久中文字幕一冢本| 精品久久久久久国产牛牛app| 国产精品欧美久久久天天影视| 亚洲精品乱码久久久久久蜜桃图片 | 亚洲国产美女精品久久久久∴| 亚洲国产高清精品线久久 | 国内精品久久九九国产精品| 亚洲AV日韩精品久久久久久久| 久久青青国产| 久久乐国产精品亚洲综合| 嫩草影院久久国产精品| 国产精品久久久久久久久| 久久精品国产亚洲AV无码娇色| 精品久久久久久国产潘金莲| 成人亚洲欧美久久久久| 国产精品99久久精品| 亚洲伊人久久大香线蕉苏妲己| 亚洲国产精品一区二区久久|