| 79 | } |
| 80 | |
| 81 | public static void main(String[] args) throws IOException { |
| 82 | BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); |
| 83 | StreamTokenizer in = new StreamTokenizer(br); |
| 84 | PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out)); |
| 85 | in.nextToken(); |
| 86 | n = (int) in.nval; |
| 87 | while (n != 0) { |
| 88 | for (int i = 1; i <= n; i++) { |
| 89 | in.nextToken(); |
| 90 | x[i] = (int) in.nval; |
| 91 | in.nextToken(); |
| 92 | y[i] = (int) in.nval; |
| 93 | in.nextToken(); |
| 94 | z[i] = (int) in.nval; |
| 95 | } |
| 96 | for (int i = 1; i <= n; i++) { |
| 97 | for (int j = 1; j <= n; j++) { |
| 98 | if (i != j) { |
| 99 | dist[i][j] = Math.sqrt((x[i] - x[j]) * (x[i] - x[j]) + (y[i] - y[j]) * (y[i] - y[j])); |
| 100 | cost[i][j] = Math.abs(z[i] - z[j]); |
| 101 | } |
| 102 | } |
| 103 | } |
| 104 | double l = 0, r = 100, x, ans = 0; |
| 105 | while (l < r && r - l >= sml) { |
| 106 | x = (l + r) / 2; |
| 107 | // 如果最小生成树的权值 <= 0，达标，左侧二分找寻更小比值 |
| 108 | // 如果最小生成树的权值 > 0，不达标，右侧二分找寻更大比值 |
| 109 | if (prim(x) <= 0) { |
| 110 | ans = x; |
| 111 | r = x - sml; |
| 112 | } else { |
| 113 | l = x + sml; |
| 114 | } |
| 115 | } |
| 116 | out.printf("%.3f\n", ans); |
| 117 | in.nextToken(); |
| 118 | n = (int) in.nval; |
| 119 | } |
| 120 | out.flush(); |
| 121 | out.close(); |
| 122 | br.close(); |
| 123 | } |
| 124 | |
| 125 | } |