Description
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Input
The input contains several test cases. The first line of each test case contains an integer n(1<=n<=100000), The following n-1 lines each contains three integers u(0 <= u < n),v(0 <= v < n),w(0 <= w < 2^31), which means there is an edge between node u and v of length w.Output
For each test case output the xor-length of the xor-longest path.Sample Input
41 2 3
2 3 4
2 4 6
Sample Output
7Hint
The xor-longest path is 1->2->3, which has length 7 (=3 ⊕ 4)注意:结点下标从1开始到N....