QTREE - Query on a tree
You are given a tree (an acyclic undirected connected graph) with N nodes, and edges numbered 1, 2, 3...N-1.
We will ask you to perfrom some instructions of the following form:
- CHANGE i ti : change the cost of the i-th edge to ti
- QUERY a b : ask for the maximum edge cost on the path from node a to node b
The first line of input contains an integer t, the number of test cases (t <= 20). t test cases follow.
For each test case:
- In the first line there is an integer N (N <= 10000),
- In the next N-1 lines, the i-th line describes the i-th edge: a line with three integers a b c denotes an edge between a, b of cost c (c <= 1000000),
- The next lines contain instructions "CHANGE i ti" or "QUERY a b",
- The end of each test case is signified by the string "DONE".
There is one blank line between successive tests.
For each "QUERY" operation, write one integer representing its result.
Input: 1 3 1 2 1 2 3 2 QUERY 1 2 CHANGE 1 3 QUERY 1 2 DONE Output: 1 3
Why does my code(c++) runtime error (SIGSEGV)?Last edit: 2021-11-27 09:05:23
Well, thank you.Last edit: 2021-10-31 08:25:03
TLE in JAVA same code in CPP is ACCEPTED
AC, but HLD is just pain
Last edit: 2021-03-11 15:22:43
best place to study heavy light decompostion
Not kidding. What's HLD? Please tell me...Last edit: 2020-08-30 16:17:01
Nice problem to learn HLD :)
If you are getting RE SIGSEGV, use void return type with functions not returning anything.
There's no need to find LCA separately if you are using HLD.
|Added by:||Thanh-Vy Hua|
|Cluster:||Cube (Intel G860)|
|Languages:||ADA95 ASM32 BASH BF C CSHARP CPP CLPS LISP sbcl LISP clisp D FORTRAN HASK ICON ICK JAVA LUA NEM NICE OCAML PAS-GPC PAS-FPC PERL PHP PIKE PRLG-swi PYTHON RUBY SCM qobi SCM guile ST TEXT WHITESPACE|