Submission #133893

# Submission time Handle Problem Language Result Execution time Memory
133893 2019-07-21T16:36:03 Z nvmdava Simurgh (IOI17_simurgh) C++17
0 / 100
2 ms 376 KB
#include "simurgh.h"
#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define N 505

vector<int> inq, tree, ACpls, adj[N], cyc, fin, onn, off, vall, imsad;
vector<pair<int, int> > edge;
int n, m, par[N], dep[N], p[N], t;
bool ans[150000], ch[150000], in[N];

int get(int v, int i){
	return edge[i].ff + edge[i].ss - v;
}

void reset(){
	for(int i = 0; i < n; i++)
		p[i] = i;
}

int find(int v){
	return v == p[v] ? v : p[v] = find(p[v]);
}

bool merge(int v, int u){
	v = find(v);
	u = find(u);
	if(v == u) return 0;
	p[v] = u;
	return 1;
}

int ask(){
	reset();
	for(int& x : inq)
		merge(edge[x].ff, edge[x].ss);
	t = 0;
	for(int& x : tree){
		if(merge(edge[x].ff, edge[x].ss)){
			inq.pb(x);
			t += ans[x];
		}
	}
	return count_common_roads(inq);
}

void dfs(int v){
	for(int& x : adj[v]){
		int u = get(v, x);
		if(dep[u]) continue;
		par[u] = x;
		dep[u] = dep[v] + 1;
		tree.pb(x);
		dfs(u);
	}
}

int fillexc(int x){
	inq = cyc;
	for(int& a : inq){
		if(a == x){
			swap(a, inq.back());
			inq.pop_back();
			break;
		}
	}
	return ask();
}

void solvecycle(){
	if(fin.empty()) return;
	if(onn.empty() && off.empty()){
		int lo = -1;
		vall.clear();
		for(int& x : cyc)
			vall.pb(fillexc(x));
		for(int& x : vall)
			lo = max(lo, x);
		for(int i = cyc.size() - 1; i >= 0; i--){
			ch[cyc[i]] = 1;
			ans[cyc[i]] = (lo - vall[i]);
		}
	} else {
		int lo;
		if(off.empty())
			lo = fillexc(onn[0]);
		else 
			lo = fillexc(off[0]) - 1;
		for(int& x : fin){
			ch[x] = 1;
			ans[x] = (fillexc(x) == lo);
		}
	}
}

void solvetree(){
	for(int i = 0; i < m; i++){
		if(dep[edge[i].ff] < dep[edge[i].ss]) swap(edge[i].ff, edge[i].ss);
		if(dep[edge[i].ff] - dep[edge[i].ss] == 1) continue;
		cyc.clear(); fin.clear(); off.clear(); onn.clear();
		cyc.pb(i);
		int s = edge[i].ff;
		while(s != edge[i].ss){
			cyc.pb(par[s]);
			if(ch[par[s]] == 0) fin.pb(par[s]);
			else if(ans[par[s]] == 1) onn.pb(par[s]);
			else off.pb(par[s]);
			s = get(s, par[s]);
		}
		solvecycle();
	}
	for(int& x : tree){
		if(ch[x] == 0){
			ch[x] = ans[x] = 1;
		}
	}
}

void dfs2(int v){
	in[v] = 1;
	for(int i = adj[v].size() - 1; i >= 0; i--){
		if(ch[adj[v][i]]){
			swap(adj[v][i], adj[v].back());
			adj[v].pop_back();
			continue;
		}
		int u = get(v, adj[v][i]);
		if(in[u]) continue;
		imsad.pb(adj[v][i]);
		dfs2(u);
	}
}

void solvethisshit(){
	if(imsad.empty()) return;
	inq = imsad;
	if(ask() == t){
		for(int& x : imsad){
			ch[x] = 1;
			ans[x] = 0;
		}
		return;
	}
	int l = 0, r = imsad.size() - 1;
	while(l != r){
		int m = (l + r) >> 1;
		inq.clear();
		for(int i = 0; i <= m; i++)
			inq.pb(imsad[i]);
		if(ask() == t) l = m + 1;
		else r = m;
	}
	for(int i = 0; i < r; i++){
		ch[imsad[i]] = 1;
		ans[imsad[i]] = 0;
	}
	ch[imsad[r]] = ans[imsad[r]] = 1;
}


vector<int> find_roads(int n, vector<int> u, vector<int> v) {
	::n = n;
	m = u.size();
	for(int i = 0; i < m; i++){
		adj[v[i]].pb(i);
		adj[u[i]].pb(i);
		edge.pb({v[i], u[i]});
	}
	dep[0] = 1;
	dfs(0);
	if(m == n - 1){
		return tree; 
	}
	solvetree();
	do{
		memset(in, 0, sizeof in);
		imsad.clear();
		for(int i = 0; i < n; i++){
			if(in[i]) continue;
			dfs2(i);
		}
		solvethisshit();
	} while(!imsad.empty());
	return ACpls;
}
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 376 KB WA in grader: NO
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 376 KB WA in grader: NO
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 376 KB WA in grader: NO
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB correct
2 Incorrect 2 ms 376 KB WA in grader: NO
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 376 KB WA in grader: NO
2 Halted 0 ms 0 KB -