Hlju 1105 CPC meow split set (and query the reverse operation of the Set)

1105: split set of meow
Time Limit: 1 sec memory limit: 128 MB
Submit: 37 solved: 8
[Submit] [Status] [web board] Description

As we all know, doubleq is a DS (Data Structure) powder, and she loves DS most. Now she wants to implement a magic DS and supports the following two operations:
-Delete an edge, expressed as "d x", that is, delete the X edge.
-Check whether two points belong to a set, expressed as "q a B", that is, whether node A and Node B are in the same set. If they are in the same set, output "yes"; otherwise output "NO" (the output does not include quotation marks)

N <= 100000, m <= 100000, q <= 100000

Input

Multiple groups of data.

For each group of data, the first row contains three positive integers, representing the number of nodes in the data structure N, the number of edges m, and the operand Q

The next m row represents the I edge (starting from 1), and the I edge connects the u and v vertices (no duplicate edge, no self ring)
The next row of the Q-row contains a format such as the question description operation.

Output

For each query, the output includes one row, indicating the query result. That is, if two points belong to the same set, "yes" is output; otherwise, "no" is output ".

Sample Input

5 4 61 22 34 51 3Q 1 2D 1Q 1 2Q 3 4D 2Q 1 2

Sample output

YesYesNoNo

Resolution: reverse processing. Because edge deletion is not easy to implement, we can change our thinking. All operations are retained first, and then each operation is executed in reverse order. In this way, deleting an edge is equivalent to not adding this edge, and then performing each operation in reverse order.

AC code:

# Include <cstdio> # include <cstring> # include <iostream> # include <algorithm> using namespace STD; const int maxn = 100000 + 10; typedef struct node {int, b;} edge; edge e [maxn], Q [maxn]; int del [maxn], is_d [maxn]; bool s [maxn]; int par [maxn]; // father [] array char op [maxn] [4]; // Save the inline int getpar (int x) {return x = par [x]? X: par [x] = getpar (par [x]);} inline void unin (int x, int y) {int A = getpar (x ), B = getpar (y); if (! = B) par [a] = B;} int main () {# ifdef sxk freopen ("in.txt", "r", stdin); # endif // sxk STD :: IOS: sync_with_stdio (false); STD: cin. tie (0); int n, m, K; while (scanf ("% d", & N, & M, & K )! = EOF) {memset (is_d, 0, sizeof (is_d); memset (S, false, sizeof (s); memset (E, 0, sizeof (e )); memset (Q, 0, sizeof (q); memset (Del, 0, sizeof (DEL); For (INT I = 1; I <= N; I ++) {Par [I] = I ;}for (INT I = 1; I <= m; I ++) {scanf ("% d ", & E [I]. a, & E [I]. b);} int fo = 0, foo = 0; For (INT I = 1; I <= K; I ++) {scanf ("% s ", & OP [I]); If (OP [I] [0] = 'q') {Foo ++; scanf ("% d ", & Q [Foo]. a, & Q [Foo]. b) ;}else {fo ++; scanf (" % D ", & del [fO]); is_d [del [fO] = 1 ;}}for (INT I = 1; I <= m; I ++) {If (! Is_d [I]) unin (E [I]. a, E [I]. b);} int CNT = Foo; For (INT I = K; I> 0; I --) {If (OP [I] [0] = 'q ') {If (getpar (Q [CNT]. a) = getpar (Q [CNT]. b) s [CNT] = true; else s [CNT] = false; CNT --;} else {unin (E [del [fO]. a, E [del [fO]. b); fo -- ;}}for (INT I = 1; I <= Foo; I ++) printf ("% s \ n ", s [I] = true? "Yes": "no");} return 0 ;}

Hlju 1105 CPC meow split set (and query the reverse operation of the Set)