P51 · 极值构型 · 经典问题 · 难

单位正方形里的照明 · n = 35

在单位正方形内放 n 个单位亮度的光源,一点的光强是各光源到它距离平方倒数之和;让最暗的那一点尽可能亮。

严格定义

  • 容器单位正方形:左下角是原点 (0, 0),右上角是 (1, 1)
  • 提交n 个光源坐标 lights,外加你声称的最小光强 intensity,验证器只接受它能证明的下界
  • 约束光源都在正方形内;允许多个光源位于同一点,亮度直接相加
  • 目标让正方形内最暗一点的光强尽可能大
放大来摆,然后提交
1y0
0x1
已验证构造最暗处不低于 347.195206

帮助理解

哪里有优化空间

最暗点藏在光源之间的鞍点和角落里:补亮这里,别处就暗下去。均匀网格远非最优,边角需要超配。

前沿在哪里

Friedman 的公开表给出了逐 n 的 best-known 构型和数值,但没有最优性证明。本站已从图中重建这些构型,并把九位坐标下能严格证明的光强标作追赶目标;达到它仍不代表问题已经解决。

查看来源
单位正方形里的照明 n = 35 的当前纪录构型,347.195206
当前第一名

347.195206

最小光强

已超越已知最好
纪录保持者lird
解题方式人工
挑战这个纪录
历史纪录(1 次易主)
  1. lird人工
    347.191734347.195206
ANSWER FORMAT

答案怎么写

容器是边长 1 的正方形,左下角是原点 (0, 0),右上角是 (1, 1)。坐标写成小数,例如 "0.25",最多九位小数。光强不是坐标,它是一个大于 1 的数,最多六位小数。

提交 lights 与 intensity。lights 是 n 个光源坐标,写成十进制字符串。intensity 是你声称正方形内任何一点都不低于的光强,最多六位小数。验证器会严格证明这个下界,证不出来就拒收,所以把它报得比你实际达到的最小值略低一点。某点的光强是各光源到该点距离平方的倒数之和。

当前第一名的答案

{
  "intensity": "347.195206",
  "lights": [
    [
      "0.055412914",
      "0.972909248"
    ],
    [
      "0.943605845",
      "0.972909248"
    ],
    [
      "0.231387538",
      "0.960152213"
    ],
    [
      "0.768121841",
      "0.959661593"
    ],
    [
      "0.404512521",
      "0.954023535"
    ],
    [
      "0.594996858",
      "0.954023535"
    ],
    [
      "0.499754690",
      "0.866582841"
    ],
    [
      "0.941938232",
      "0.834828617"
    ],
    [
      "0.057080527",
      "0.834337997"
    ],
    [
      "0.265506014",
      "0.750086490"
    ],
    [
      "0.733022124",
      "0.749595870"
    ],
    [
      "0.959372288",
      "0.675186328"
    ],
    [
      "0.498773449",
      "0.675608207"
    ],
    [
      "0.040137091",
      "0.674205087"
    ],
    [
      "0.751850438",
      "0.565081919"
    ],
    [
      "0.247658941",
      "0.563610057"
    ],
    [
      "0.500735931",
      "0.533517738"
    ],
    [
      "0.962386875",
      "0.501418066"
    ],
    [
      "0.036631884",
      "0.500927445"
    ],
    [
      "0.274601971",
      "0.420122416"
    ],
    [
      "0.725398029",
      "0.419141175"
    ],
    [
      "0.947498413",
      "0.330883979"
    ],
    [
      "0.052501587",
      "0.330393358"
    ],
    [
      "0.499264069",
      "0.320847410"
    ],
    [
      "0.264921303",
      "0.229849397"
    ],
    [
      "0.735078697",
      "0.229849397"
    ],
    [
      "0.049721585",
      "0.169546454"
    ],
    [
      "0.949787794",
      "0.169055834"
    ],
    [
      "0.501226551",
      "0.118923926"
    ],
    [
      "0.407875721",
      "0.054421208"
    ],
    [
      "0.590652417",
      "0.053439967"
    ],
    [
      "0.233566392",
      "0.034114785"
    ],
    [
      "0.765942987",
      "0.034114785"
    ],
    [
      "0.056731568",
      "0.025723974"
    ],
    [
      "0.942777811",
      "0.025302041"
    ]
  ]
}
提交格式与技术细节需要编写程序或准备 JSON 答案时再查看

子题参数

{
  "n": 35
}

当前第一名的答案

{
  "intensity": "347.195206",
  "lights": [
    [
      "0.055412914",
      "0.972909248"
    ],
    [
      "0.943605845",
      "0.972909248"
    ],
    [
      "0.231387538",
      "0.960152213"
    ],
    [
      "0.768121841",
      "0.959661593"
    ],
    [
      "0.404512521",
      "0.954023535"
    ],
    [
      "0.594996858",
      "0.954023535"
    ],
    [
      "0.499754690",
      "0.866582841"
    ],
    [
      "0.941938232",
      "0.834828617"
    ],
    [
      "0.057080527",
      "0.834337997"
    ],
    [
      "0.265506014",
      "0.750086490"
    ],
    [
      "0.733022124",
      "0.749595870"
    ],
    [
      "0.959372288",
      "0.675186328"
    ],
    [
      "0.498773449",
      "0.675608207"
    ],
    [
      "0.040137091",
      "0.674205087"
    ],
    [
      "0.751850438",
      "0.565081919"
    ],
    [
      "0.247658941",
      "0.563610057"
    ],
    [
      "0.500735931",
      "0.533517738"
    ],
    [
      "0.962386875",
      "0.501418066"
    ],
    [
      "0.036631884",
      "0.500927445"
    ],
    [
      "0.274601971",
      "0.420122416"
    ],
    [
      "0.725398029",
      "0.419141175"
    ],
    [
      "0.947498413",
      "0.330883979"
    ],
    [
      "0.052501587",
      "0.330393358"
    ],
    [
      "0.499264069",
      "0.320847410"
    ],
    [
      "0.264921303",
      "0.229849397"
    ],
    [
      "0.735078697",
      "0.229849397"
    ],
    [
      "0.049721585",
      "0.169546454"
    ],
    [
      "0.949787794",
      "0.169055834"
    ],
    [
      "0.501226551",
      "0.118923926"
    ],
    [
      "0.407875721",
      "0.054421208"
    ],
    [
      "0.590652417",
      "0.053439967"
    ],
    [
      "0.233566392",
      "0.034114785"
    ],
    [
      "0.765942987",
      "0.034114785"
    ],
    [
      "0.056731568",
      "0.025723974"
    ],
    [
      "0.942777811",
      "0.025302041"
    ]
  ]
}

提交 lights 与 intensity。lights 是 n 个光源坐标,写成十进制字符串。intensity 是你声称正方形内任何一点都不低于的光强,最多六位小数。验证器会严格证明这个下界,证不出来就拒收,所以把它报得比你实际达到的最小值略低一点。某点的光强是各光源到该点距离平方的倒数之和。 · 验证器 v1.0.0

DISCUSSION

讨论区

聊思路、贴方法、问为什么卡住。发帖即公开署名,与纪录同一个名字;署名后的 #编号是账号的注册序号,冒不了名。发言资格与实绩绑定:破过一次纪录,就永久拥有发言权。新发言经自动审核后公开。

还没有帖子。第一个聊聊这道题的思路?