Submission #4746

# Submission time Handle Problem Language Result Execution time Memory
4746 2013-12-28T05:42:36 Z tncks0121 Special graph (IZhO13_specialg) C++
5 / 100
1000 ms 22688 KB
#include <stdio.h> 
#include <stdlib.h> 
#include <string.h> 
#include <memory.h> 
#include <math.h> 
#include <assert.h> 
#include <stack> 
#include <queue> 
#include <map> 
#include <set> 
#include <algorithm> 
#include <string> 
#include <functional> 
#include <vector> 
#include <deque> 
#include <utility> 
#include <bitset> 
#include <limits.h>  

using namespace std; 
typedef long long ll; 
typedef unsigned long long llu; 
typedef double lf;
typedef unsigned int uint;
typedef long double llf;
typedef pair<int, int> pii;

struct DisjointSet {
	vector<int> parent, rnk;
	DisjointSet(): parent(), rnk() { }

	void resize(uint size) { 
		parent.resize(size+1);
		rnk.resize(size+1, 1);
		for(uint i = 1; i <= size; i++) parent[i] = i;
	}

	int group (int u) {
		int ret = u;
		while(ret != parent[ret]) ret = parent[ret];
		while(u != ret) {
			int p = parent[u];
			parent[u] = ret;
			u = p;
		}
		return ret;
	}

	bool merge (int u, int v) {
		int a = group(u);
		int b = group(v);
		if(a == b) return false;
		if(rnk[a] > rnk[b]) swap(a, b);
		else if(rnk[a] == rnk[b]) ++rnk[b];
		parent[a] = b;
		return true;
	}
};

const int lgN_ = 17, N_ = 100005;
const int Q_ = 100005;

int N; // 노드 수
int Next[lgN_][N_]; // Next[k, i]: i에서 2^k만큼 갔을 때 노드 번호
vector<int> Rev[N_]; // reverse graph

int Level[N_], Root[N_];

int Q;
pii Query[Q_];
bool deleted[N_];

int CYCN;
int cycle[N_], cycle_wh[N_], cycle_length[N_];
set<pii> cycle_group[N_];

DisjointSet component;

vector<int> result;

void input() {
	scanf("%d", &N);
	for(int i = 1; i <= N; i++) scanf("%d", &Next[0][i]);
	scanf("%d", &Q);
	for(int i = 1; i <= Q; i++) {
		int q; scanf("%d", &q);
		if(q == 1) scanf("%d", &Query[i].first), Query[i].second = -1, deleted[Query[i].first] = true;
		else scanf("%d%d", &Query[i].first, &Query[i].second);
	}
}

void fillNext() {
	for(int k = 1; k < lgN_; k++)
		for(int i = 1; i <= N; i++) {
			int x = Next[k - 1][i];
			if(x == 0) continue;
			Next[k][i] = Next[k - 1][x];
		}
}

int go (int u, int len) {
	for(int k = 0; k < lgN_; k++) {
		if(u > 0 && (len & (1<<k))) u = Next[k][u];
	}
	return u;
}

void mergeComponent() {
	component.resize(N);
	for(int u = 1; u <= N; u++) {
		int v = Next[0][u];
		if(v > 0 && !deleted[u]) component.merge(u, v);
	}
}

void findCycle() {
	mergeComponent();

	vector<int> pth;
	vector<bool> visited(N+1);
	for(int s = 1; s <= N; s++) if(!cycle[s]) {
		pth.clear();
		int last = -1;
		for(int u = s; !visited[u] && u > 0; ) {
			pth.push_back(u);
			visited[u] = true;
			u = Next[0][u];
			last = u;
		}
		if(last > 0) {
			int found_x = -1;
			for(int i = 0; i < pth.size(); i++) {
				if(pth[i] == last) found_x = i, ++CYCN;
				if(found_x >= 0) cycle[pth[i]] = CYCN, cycle_wh[pth[i]] = i - found_x, 
					++cycle_length[CYCN];
			}
			int last = -1, first = -1;
			int delnd = -1;
			for(int i = found_x; i < pth.size(); i++) {
				int u = pth[i];
				int v = Next[0][u];
				if(deleted[u]) delnd = i - found_x;

				if(component.group(u) != component.group(v)) {
					if(i+1 == pth.size() && first >= 0) cycle_group[CYCN].insert(pii(0, first));
					if(last >= 0) cycle_group[CYCN].insert(pii(last+1, i));
					else first = i-found_x;
					last = i-found_x;
				}else {
					if(i+1 == pth.size()) {
						if(first >= 0) {
							if(first < last+1) first += cycle_length[CYCN];
							cycle_group[CYCN].insert(pii(last+1, first));
						}else if(delnd >= 0) { // 모두 선 하나로 연결되어 있음
							int s = (delnd + 1) % cycle_length[CYCN];
							cycle_group[CYCN].insert(pii(s, s + cycle_length[CYCN] - 1));
						}
					}
				}
			}
		}
	}
}

void fillLevel() {
	for(int u = 1; u <= N; u++) 
		if(Next[0][u] > 0) Rev[Next[0][u]].push_back(u);

	queue<int> que;
	for(int s = 1; s <= N; s++) if(cycle[s] || Next[0][s] == 0) {
		while(!que.empty()) que.pop();
		que.push(s); que.push(-1); Root[s] = s;
		while(!que.empty()) {
			int u = que.front(); que.pop();
			int p = que.front(); que.pop();
			for(int e = 0; e < Rev[u].size(); e++) {
				int v = Rev[u][e];
				if(v != p && !cycle[v]) {
					Level[v] = Level[u] + 1;
					Root[v] = s;
					que.push(v); que.push(u);
				}
			}
		}
	}
}

void solveQuery() {

	for(int q = Q; q > 0; q--) {
		int u = Query[q].first, v = Query[q].second;
		if(v == -1) {
			v = Next[0][u];
			component.merge(u, v);
			int c = cycle[u];
			deleted[u] = 0;

			if(c > 0) {
				set<pii>& gr = cycle_group[c];
				if(gr.size() <= 1) {
					gr.clear();
				}else {
					set<pii>::iterator itv = gr.lower_bound( pii(cycle_wh[v], cycle_wh[v]) );
					set<pii>::iterator itu = itv; 
					if(itu == gr.begin()) itu = gr.end();
					--itu;

					int ua = itu->first, ub = itu->second;
					int va = itv->first, vb = itv->second;

					gr.erase(itu);
					gr.erase(itv);
					if(vb < ua) vb += cycle_length[c];
					gr.insert( pii(ua, vb) );
				}
			}
		}else {
			int ret = 0, a = u, b = v;
			if(component.group(u) == component.group(v)) {
				bool is_u_cycle = (cycle[u] > 0);
				bool is_v_cycle = (cycle[v] > 0);

				if(!is_u_cycle && !is_v_cycle) {
					int len = Level[u] - Level[v];
					if(len >= 0 && go(u, len) == v) ret = len;
				}else if(!is_u_cycle && is_v_cycle) {
					int len = Level[u] - Level[Root[u]];
					if(len >= 0 && go(u, len) == Root[u]) ret = len;
					u = Root[u]; is_u_cycle = true;
				}

				if(is_u_cycle && is_v_cycle) {
					if(cycle_group[cycle[u]].empty()) {
						int len = cycle_wh[v] - cycle_wh[u];
						if(len < 0) len += cycle_length[cycle[u]];
						ret += len;
					}else {
						int uw1 = cycle_wh[u], uw2 = uw1 + cycle_length[cycle[u]];
						set<pii>& gr = cycle_group[cycle[u]];

						set<pii>::iterator it1 = gr.lower_bound ( pii(uw1, uw1) );
						if(it1 == gr.end()) it1--;
						while(it1 != gr.end() && !(it1->first <= uw1 && uw1 <= it1->second) && it1->second >= uw1) it1--;

						set<pii>::iterator it2 = gr.lower_bound ( pii(uw2, uw2) );
						if(it2 == gr.end()) it2--;
						while(it2 != gr.end() && !(it2->first <= uw2 && uw2 <= it2->second) && it2->second >= uw2) it2--;

						set<pii>::iterator it = (it1 != gr.end()) ? it1 : it2;
						if(it == gr.end()) ret = -1;
						else {
							int uw = (it1 != gr.end()) ? uw1 : uw2;
							if(it->first <= cycle_wh[v] && cycle_wh[v] <= it->second) {
								if(cycle_wh[v] >= uw) ret += cycle_wh[v] - uw;
								else ret = -1;
							}else if(it->first <= cycle_wh[v] + cycle_length[cycle[u]] && cycle_wh[v] + cycle_length[cycle[u]] <= it->second) {
								if(cycle_wh[v] + cycle_length[cycle[u]] >= uw) ret += cycle_wh[v] + cycle_length[cycle[u]] - uw;
								else ret = -1;
							}else {
								ret = -1;
							}
						}
					}
				}
			}
			if(a == b) ret = 0;
			else if(ret == 0) ret = -1;
			result.push_back(ret);
		}
	}
}

void output() {
	reverse(result.begin(), result.end());
	for(int i = 0; i < result.size(); i++) printf("%d\n", result[i]);
}

int main() {
	int i;

	input();
	
	fillNext();
	findCycle();
	fillLevel();
	
	solveQuery();

	output();

	return 0;
}
# Verdict Execution time Memory Grader output
1 Execution timed out 1000 ms 17752 KB Program timed out
2 Execution timed out 1000 ms 17752 KB Program timed out
3 Execution timed out 1000 ms 17752 KB Program timed out
4 Execution timed out 1000 ms 17912 KB Program timed out
5 Execution timed out 1000 ms 17752 KB Program timed out
6 Execution timed out 1000 ms 17752 KB Program timed out
7 Execution timed out 1000 ms 17752 KB Program timed out
8 Execution timed out 1000 ms 17752 KB Program timed out
9 Execution timed out 1000 ms 17924 KB Program timed out
10 Execution timed out 1000 ms 17932 KB Program timed out
11 Correct 76 ms 22688 KB Output is correct
12 Execution timed out 1000 ms 19536 KB Program timed out
13 Execution timed out 1000 ms 20224 KB Program timed out
14 Execution timed out 1000 ms 19344 KB Program timed out
15 Execution timed out 1000 ms 19692 KB Program timed out
16 Execution timed out 1000 ms 19544 KB Program timed out
17 Execution timed out 1000 ms 20924 KB Program timed out
18 Execution timed out 1000 ms 20924 KB Program timed out
19 Execution timed out 1000 ms 20924 KB Program timed out
20 Execution timed out 1000 ms 22176 KB Program timed out