| 61 | } |
| 62 | |
| 63 | public static void main(String[] args) throws IOException { |
| 64 | BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); |
| 65 | StreamTokenizer in = new StreamTokenizer(br); |
| 66 | PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out)); |
| 67 | in.nextToken(); |
| 68 | n = (int) in.nval; |
| 69 | while (n != 0) { |
| 70 | for (int i = 1; i <= n; i++) { |
| 71 | in.nextToken(); |
| 72 | x[i] = (int) in.nval; |
| 73 | in.nextToken(); |
| 74 | y[i] = (int) in.nval; |
| 75 | in.nextToken(); |
| 76 | z[i] = (int) in.nval; |
| 77 | } |
| 78 | for (int i = 1; i <= n; i++) { |
| 79 | for (int j = 1; j <= n; j++) { |
| 80 | if (i != j) { |
| 81 | dist[i][j] = Math.sqrt((x[i] - x[j]) * (x[i] - x[j]) + (y[i] - y[j]) * (y[i] - y[j])); |
| 82 | cost[i][j] = Math.abs(z[i] - z[j]); |
| 83 | } |
| 84 | } |
| 85 | } |
| 86 | double l = 0, r = 100, x; |
| 87 | // 二分进行60次，足够达到题目要求的精度 |
| 88 | // 二分完成后，l就是答案 |
| 89 | for (int i = 1; i <= 60; i++) { |
| 90 | x = (l + r) / 2; |
| 91 | if (prim(x) <= 0) { |
| 92 | r = x; |
| 93 | } else { |
| 94 | l = x; |
| 95 | } |
| 96 | } |
| 97 | out.printf("%.3f\n", l); |
| 98 | in.nextToken(); |
| 99 | n = (int) in.nval; |
| 100 | } |
| 101 | out.flush(); |
| 102 | out.close(); |
| 103 | br.close(); |
| 104 | } |
| 105 | |
| 106 | } |