P05 · 装箱与覆盖 · 经典问题 · 难

可倾斜等正方形装入圆 · n = 29

文献中也称squares in circlespacking unit squares in a circle

在半径 1 的圆内放 n 个可任意旋转的正方形,边长完全相同、互不重叠,使共同边长尽可能大。

子题n = 29
目标最大化 最小边长

严格定义

  • 容器半径 1 的圆,圆心在 (1, 1),两个坐标都在 0 到 2 之间
  • 提交每个正方形写 {cx, cy, ux, uy}:中心加一条半边向量,另一条固定取 (−uy, ux)
  • 约束每个正方形的角度完全自由;全部落在容器内;两两内部不重叠,贴边接触允许。计分只看最小的那个正方形,所以边长不一致占不到便宜
  • 目标让共同边长尽可能大。内部以其平方精确比较
放大来摆,然后提交
2y0
0x2
已验证构造29 个正方形

帮助理解

哪里有优化空间

圆形容器没有角:正方形的直边贴不住弧形边界,最优解几乎总是倾斜的,正方形彼此以角相抵。

前沿在哪里

n = 4 已证明;n ≤ 35 的其余已知最好值取自 Friedman 的 squares-in-circles 汇总(1997 年起多人贡献),全部未证明;n = 36–40 没有任何公开记录,从零开始。

查看来源
可倾斜等正方形装入圆 n = 29 的当前纪录构型,0.294715695
当前第一名

0.294715695

最小边长

答案来源Milan Kovacic
解题方式公开参考构造
挑战这个纪录 提交证明 / 思路 在讨论区分享证明或思路,审核采纳后可获得证明分。
纪录保持者的求解笔记暂无求解笔记(点击展开)

纪录保持者还没有分享求解过程。

ANSWER FORMAT

答案怎么写

容器是半径 1 的圆,圆心在 (1, 1),所以坐标范围是 0 到 2。坐标和向量用同一个单位,直接写成小数,例如 "0.4",最多九位小数。

每个正方形提交 {cx,cy,ux,uy}:中心加一条半边向量,另一条半边向量固定取 (-uy,ux)。每个数写成十进制字符串,例如 "0.4";角度完全自由,计分取最小正方形的边长,所以把它们写得一样大最划算。边长本身几乎总是无理数,写不成有限小数,所以你写的是那条半边向量,边长由它精确定出。

当前第一名的答案

{
  "squares": [
    {
      "cx": "1.314920902",
      "cy": "0.543981357",
      "ux": "0.147355668",
      "uy": "-0.000801661"
    },
    {
      "cx": "0.876471872",
      "cy": "0.834523107",
      "ux": "0.147355668",
      "uy": "-0.000801641"
    },
    {
      "cx": "0.311392597",
      "cy": "1.417861844",
      "ux": "0.117239173",
      "uy": "0.089271001"
    },
    {
      "cx": "0.828196930",
      "cy": "1.772984498",
      "ux": "0.085727547",
      "uy": "0.119854592"
    },
    {
      "cx": "0.490072901",
      "cy": "1.669683271",
      "ux": "0.117239172",
      "uy": "0.089271003"
    },
    {
      "cx": "1.024937689",
      "cy": "1.541455635",
      "ux": "0.085727545",
      "uy": "0.119854593"
    },
    {
      "cx": "1.675811683",
      "cy": "1.438254983",
      "ux": "0.085727517",
      "uy": "0.119854613"
    },
    {
      "cx": "0.681556271",
      "cy": "1.445058918",
      "ux": "0.117239189",
      "uy": "0.089270981"
    },
    {
      "cx": "1.196392817",
      "cy": "1.781164893",
      "ux": "0.085727544",
      "uy": "0.119854594"
    },
    {
      "cx": "0.495943858",
      "cy": "1.142052641",
      "ux": "0.138153541",
      "uy": "0.051263384"
    },
    {
      "cx": "1.007180417",
      "cy": "0.512792242",
      "ux": "0.014265249",
      "uy": "0.146665736"
    },
    {
      "cx": "1.618441021",
      "cy": "0.500991344",
      "ux": "0.012650734",
      "uy": "0.146813808"
    },
    {
      "cx": "1.818334270",
      "cy": "1.075382562",
      "ux": "0.012650733",
      "uy": "0.146813809"
    },
    {
      "cx": "1.791804044",
      "cy": "0.781860775",
      "ux": "0.012650734",
      "uy": "0.146813808"
    },
    {
      "cx": "1.515697803",
      "cy": "1.130225505",
      "ux": "0.026013921",
      "uy": "0.145043481"
    },
    {
      "cx": "1.488967865",
      "cy": "0.835601233",
      "ux": "0.026013923",
      "uy": "0.145043481"
    },
    {
      "cx": "1.489685316",
      "cy": "1.684623775",
      "ux": "0.085727542",
      "uy": "0.119854595"
    },
    {
      "cx": "1.318230159",
      "cy": "1.444914526",
      "ux": "0.085727544",
      "uy": "0.119854594"
    },
    {
      "cx": "0.538894356",
      "cy": "0.843639088",
      "ux": "0.138153541",
      "uy": "0.051263383"
    },
    {
      "cx": "1.291864963",
      "cy": "0.249386675",
      "ux": "0.147355668",
      "uy": "-0.000801661"
    },
    {
      "cx": "0.713848865",
      "cy": "0.541322748",
      "ux": "0.014265249",
      "uy": "0.146665736"
    },
    {
      "cx": "0.217269356",
      "cy": "0.762853261",
      "ux": "0.146920506",
      "uy": "0.011344613"
    },
    {
      "cx": "0.399529935",
      "cy": "0.481333645",
      "ux": "0.146920507",
      "uy": "0.011344610"
    },
    {
      "cx": "0.696236975",
      "cy": "0.246929221",
      "ux": "0.014265250",
      "uy": "0.146665736"
    },
    {
      "cx": "0.851345634",
      "cy": "1.129379895",
      "ux": "0.147355668",
      "uy": "-0.000801641"
    },
    {
      "cx": "0.176652984",
      "cy": "1.055310166",
      "ux": "0.146920507",
      "uy": "0.011344608"
    },
    {
      "cx": "1.146092744",
      "cy": "1.134340125",
      "ux": "0.147355668",
      "uy": "-0.000801642"
    },
    {
      "cx": "0.996650177",
      "cy": "0.158464233",
      "ux": "0.147355667",
      "uy": "-0.000801684"
    },
    {
      "cx": "1.171218999",
      "cy": "0.839483289",
      "ux": "0.147355668",
      "uy": "-0.000801642"
    }
  ]
}
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": 29
}

当前第一名的答案

{
  "squares": [
    {
      "cx": "1.314920902",
      "cy": "0.543981357",
      "ux": "0.147355668",
      "uy": "-0.000801661"
    },
    {
      "cx": "0.876471872",
      "cy": "0.834523107",
      "ux": "0.147355668",
      "uy": "-0.000801641"
    },
    {
      "cx": "0.311392597",
      "cy": "1.417861844",
      "ux": "0.117239173",
      "uy": "0.089271001"
    },
    {
      "cx": "0.828196930",
      "cy": "1.772984498",
      "ux": "0.085727547",
      "uy": "0.119854592"
    },
    {
      "cx": "0.490072901",
      "cy": "1.669683271",
      "ux": "0.117239172",
      "uy": "0.089271003"
    },
    {
      "cx": "1.024937689",
      "cy": "1.541455635",
      "ux": "0.085727545",
      "uy": "0.119854593"
    },
    {
      "cx": "1.675811683",
      "cy": "1.438254983",
      "ux": "0.085727517",
      "uy": "0.119854613"
    },
    {
      "cx": "0.681556271",
      "cy": "1.445058918",
      "ux": "0.117239189",
      "uy": "0.089270981"
    },
    {
      "cx": "1.196392817",
      "cy": "1.781164893",
      "ux": "0.085727544",
      "uy": "0.119854594"
    },
    {
      "cx": "0.495943858",
      "cy": "1.142052641",
      "ux": "0.138153541",
      "uy": "0.051263384"
    },
    {
      "cx": "1.007180417",
      "cy": "0.512792242",
      "ux": "0.014265249",
      "uy": "0.146665736"
    },
    {
      "cx": "1.618441021",
      "cy": "0.500991344",
      "ux": "0.012650734",
      "uy": "0.146813808"
    },
    {
      "cx": "1.818334270",
      "cy": "1.075382562",
      "ux": "0.012650733",
      "uy": "0.146813809"
    },
    {
      "cx": "1.791804044",
      "cy": "0.781860775",
      "ux": "0.012650734",
      "uy": "0.146813808"
    },
    {
      "cx": "1.515697803",
      "cy": "1.130225505",
      "ux": "0.026013921",
      "uy": "0.145043481"
    },
    {
      "cx": "1.488967865",
      "cy": "0.835601233",
      "ux": "0.026013923",
      "uy": "0.145043481"
    },
    {
      "cx": "1.489685316",
      "cy": "1.684623775",
      "ux": "0.085727542",
      "uy": "0.119854595"
    },
    {
      "cx": "1.318230159",
      "cy": "1.444914526",
      "ux": "0.085727544",
      "uy": "0.119854594"
    },
    {
      "cx": "0.538894356",
      "cy": "0.843639088",
      "ux": "0.138153541",
      "uy": "0.051263383"
    },
    {
      "cx": "1.291864963",
      "cy": "0.249386675",
      "ux": "0.147355668",
      "uy": "-0.000801661"
    },
    {
      "cx": "0.713848865",
      "cy": "0.541322748",
      "ux": "0.014265249",
      "uy": "0.146665736"
    },
    {
      "cx": "0.217269356",
      "cy": "0.762853261",
      "ux": "0.146920506",
      "uy": "0.011344613"
    },
    {
      "cx": "0.399529935",
      "cy": "0.481333645",
      "ux": "0.146920507",
      "uy": "0.011344610"
    },
    {
      "cx": "0.696236975",
      "cy": "0.246929221",
      "ux": "0.014265250",
      "uy": "0.146665736"
    },
    {
      "cx": "0.851345634",
      "cy": "1.129379895",
      "ux": "0.147355668",
      "uy": "-0.000801641"
    },
    {
      "cx": "0.176652984",
      "cy": "1.055310166",
      "ux": "0.146920507",
      "uy": "0.011344608"
    },
    {
      "cx": "1.146092744",
      "cy": "1.134340125",
      "ux": "0.147355668",
      "uy": "-0.000801642"
    },
    {
      "cx": "0.996650177",
      "cy": "0.158464233",
      "ux": "0.147355667",
      "uy": "-0.000801684"
    },
    {
      "cx": "1.171218999",
      "cy": "0.839483289",
      "ux": "0.147355668",
      "uy": "-0.000801642"
    }
  ]
}

每个正方形提交 {cx,cy,ux,uy}:中心加一条半边向量,另一条半边向量固定取 (-uy,ux)。每个数写成十进制字符串,例如 "0.4";角度完全自由,计分取最小正方形的边长,所以把它们写得一样大最划算。边长本身几乎总是无理数,写不成有限小数,所以你写的是那条半边向量,边长由它精确定出。 · 验证器 v1.0.0

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