oj.uz

Submission #50924

# Submission time Handle Problem Language Result Execution time Memory
50924 2018-06-14T22:51:18 Z Mamnoon_Siam Simurgh (IOI17_simurgh) C++17
30 / 100
 3000 ms 14684 KB 
#pragma GCC optimize("Ofast,unroll-loops,no-stack-protector")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include "simurgh.h"
#include <bits/stdc++.h>
using namespace std;

#define debug(s) cerr<< #s <<" = "<< s <<endl
#define all(v) (v).begin(), (v).end()
#define KeepUnique(v) (v).erase( unique(all(v)), v.end() )
#define MEMSET(a,val) memset(a, val, sizeof a)
#define PB push_back
#define endl '\n'

inline int myrand(int l, int r) {
	int ret = rand(); ret <<= 15; ret ^= rand();
	if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
	return ret;
}
template <typename F, typename S>
ostream& operator << (ostream& os, const pair< F, S>& p) {
    return os<<"(" <<p.first<<", "<<p.second<<")"; }

typedef pair<int, int> ii;
template<typename T> using min_pq =
	priority_queue<T, vector<T>, greater<T> >;

//int dx[] = {-1, +0, +1, +0};
//int dy[] = {+0, +1, +0, -1};

struct edge {
	int v, id;
	edge() {v = 0, id = 0;};
	edge(int v, int id) {
		this -> v = v;
		this -> id = id;
	}
	bool operator < (const edge &tmp) const {
		return ii(v, id) < ii(tmp.v, tmp.id);
	}
};

const int maxn = 505;

int n, m;
set<edge> g[505];
vector<ii> edges;
int pid[maxn];
bool vis[maxn], ok[maxn * maxn];
int edge_id[maxn][maxn];
bool flag = 0;
int head, tail;
bool col[maxn][maxn];
set<int> rem;

int par[maxn], sz[maxn];
int find(int u) {
	return par[u] == u ? u : par[u] = find(par[u]);
}
void unite(int u, int v) {
	col[u][v] = col[v][u] = 1;

	u = find(u), v = find(v);
	if(u == v) return ;
	if(sz[u] > sz[v]) swap(u, v);
	par[u] = v, sz[v] += sz[u];
}

void delete_edge(int id) {
	int u = edges[id].first, v = edges[id].second;
	g[u].erase(edge(v, id));
	g[v].erase(edge(u, id));
	ok[id] = 0;
	rem.erase(id);
}

void dfs(int u, int pe) {
	vis[u] = 1;
	pid[u] = pe;
	for(edge v : g[u]) {
		if(v.id == pe) continue;
		if(!vis[v.v]) {
			dfs(v.v, v.id);
		} else if(!flag) {
			flag = 1;
			tail = u, head = v.v;
		}
	}
}

void round() {
	MEMSET(vis, 0);
	flag = 0;

	// do dfs, head, tail
	dfs(0, -1);

	// extract tree edges
	vector<int> tree_edges;
	for(int i = 1; i < n; i++) {
		tree_edges.push_back(pid[i]);
	}

	// extract all edges which are cycle and tree edges
	vector<int> on_path;
	int temp_tail = tail;
	while(true) {
		on_path.push_back(pid[tail]);
		int u = edges[pid[tail]].first, v = edges[pid[tail]].second;
		tail ^= u ^ v;
		if(tail == head) break;
	} tail = temp_tail;

	// the back edge
	int bid = edge_id[head][tail];

	// extract differences
	vector<int> ask(on_path.size());
	int prev = count_common_roads(tree_edges);
	for(int i = 0; i < on_path.size(); i++) {
		vector<int> temp = tree_edges;
		temp.erase(find(all(temp), on_path[i]));
		temp.push_back(bid);
		int now = count_common_roads(temp);
		ask[i] = now - prev;
	}

	// identify the colours
	int allz = 1, mode_val;
	for(int i = 0; i < on_path.size(); i++) {
		if(ask[i] != 0) allz = 0, mode_val = ask[i];
	}
	if(allz) {
		for(int b : on_path) {
			delete_edge(b);
		} delete_edge(bid);
		// all are white
	} else {
		if(mode_val == -1) {
			delete_edge(bid);
			// which on_path are -1, they are black
			for(int i = 0; i < on_path.size(); i++) {
				int u = edges[on_path[i]].first, v = edges[on_path[i]].second;
				if(ask[i] == -1) {
					unite(u, v);
				}
			}
		} else {
			for(int i = 0; i < on_path.size(); i++) {
				if(ask[i] == +1) {
					delete_edge(on_path[i]);
				} // those who are +1 are white
			} // bid is black
			int u = edges[bid].first, v = edges[bid].second;
			unite(u, v);
		}
	}
}

int live_edges() {
	int ret = 0;
	for(int i = 0; i < edges.size(); i++) {
		ret += ok[i];
	} return ret;
}

vector<int> find_roads(int N, vector<int> U, vector<int> V) {
	n = N;
	for(int i = 0; i < U.size(); i++) {
		g[U[i]].insert(edge(V[i], i));
		g[V[i]].insert(edge(U[i], i));
		edges.push_back(ii(U[i], V[i]));
		edge_id[U[i]][V[i]] = i;
		edge_id[V[i]][U[i]] = i;
	}
	for(int i = 0; i < n; i++) {
		par[i] = i, sz[i] = 1;
	}
	for(int i = 0; i < U.size(); i++)
		ok[i] = 1, rem.insert(i);

	while(live_edges() >= n) {
		round();
		for(int i : rem) {
			int u = edges[i].first, v = edges[i].second;
			if(ok[i] and !col[u][v] and find(u) == find(v)) {
				delete_edge(i);
			}
		}
	}

	vector<int> ret;
	for(int i = 0; i < edges.size(); i++) {
		if(ok[i]) ret.push_back(i);
	} return ret;
}

Compilation message

simurgh.cpp: In function 'int myrand(int, int)':
simurgh.cpp:17:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
  ^~
simurgh.cpp:17:26: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
                          ^~~
simurgh.cpp: In function 'void round()':
simurgh.cpp:120:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < on_path.size(); i++) {
                 ~~^~~~~~~~~~~~~~~~
simurgh.cpp:130:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < on_path.size(); i++) {
                 ~~^~~~~~~~~~~~~~~~
simurgh.cpp:142:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int i = 0; i < on_path.size(); i++) {
                   ~~^~~~~~~~~~~~~~~~
simurgh.cpp:149:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int i = 0; i < on_path.size(); i++) {
                   ~~^~~~~~~~~~~~~~~~
simurgh.cpp: In function 'int live_edges()':
simurgh.cpp:162:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < edges.size(); i++) {
                 ~~^~~~~~~~~~~~~~
simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:169:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < U.size(); i++) {
                 ~~^~~~~~~~~~
simurgh.cpp:179:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < U.size(); i++)
                 ~~^~~~~~~~~~
simurgh.cpp:193:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < edges.size(); i++) {
                 ~~^~~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB correct
2 Correct 3 ms 544 KB correct
3 Correct 3 ms 620 KB correct
4 Correct 3 ms 620 KB correct
5 Correct 2 ms 620 KB correct
6 Correct 2 ms 620 KB correct
7 Correct 2 ms 676 KB correct
8 Correct 2 ms 676 KB correct
9 Correct 2 ms 676 KB correct
10 Correct 2 ms 676 KB correct
11 Correct 3 ms 676 KB correct
12 Correct 2 ms 676 KB correct
13 Correct 2 ms 676 KB correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB correct
2 Correct 3 ms 544 KB correct
3 Correct 3 ms 620 KB correct
4 Correct 3 ms 620 KB correct
5 Correct 2 ms 620 KB correct
6 Correct 2 ms 620 KB correct
7 Correct 2 ms 676 KB correct
8 Correct 2 ms 676 KB correct
9 Correct 2 ms 676 KB correct
10 Correct 2 ms 676 KB correct
11 Correct 3 ms 676 KB correct
12 Correct 2 ms 676 KB correct
13 Correct 2 ms 676 KB correct
14 Correct 26 ms 824 KB correct
15 Correct 13 ms 824 KB correct
16 Correct 15 ms 952 KB correct
17 Correct 20 ms 952 KB correct
18 Correct 5 ms 952 KB correct
19 Correct 23 ms 952 KB correct
20 Correct 12 ms 952 KB correct
21 Correct 14 ms 952 KB correct
22 Correct 10 ms 952 KB correct
23 Correct 8 ms 952 KB correct
24 Correct 10 ms 952 KB correct
25 Correct 3 ms 952 KB correct
26 Correct 11 ms 952 KB correct
27 Correct 9 ms 952 KB correct
28 Correct 5 ms 952 KB correct
29 Correct 3 ms 952 KB correct
30 Correct 9 ms 952 KB correct
31 Correct 10 ms 952 KB correct
32 Correct 10 ms 952 KB correct
33 Correct 9 ms 952 KB correct

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB correct
2 Correct 3 ms 544 KB correct
3 Correct 3 ms 620 KB correct
4 Correct 3 ms 620 KB correct
5 Correct 2 ms 620 KB correct
6 Correct 2 ms 620 KB correct
7 Correct 2 ms 676 KB correct
8 Correct 2 ms 676 KB correct
9 Correct 2 ms 676 KB correct
10 Correct 2 ms 676 KB correct
11 Correct 3 ms 676 KB correct
12 Correct 2 ms 676 KB correct
13 Correct 2 ms 676 KB correct
14 Correct 26 ms 824 KB correct
15 Correct 13 ms 824 KB correct
16 Correct 15 ms 952 KB correct
17 Correct 20 ms 952 KB correct
18 Correct 5 ms 952 KB correct
19 Correct 23 ms 952 KB correct
20 Correct 12 ms 952 KB correct
21 Correct 14 ms 952 KB correct
22 Correct 10 ms 952 KB correct
23 Correct 8 ms 952 KB correct
24 Correct 10 ms 952 KB correct
25 Correct 3 ms 952 KB correct
26 Correct 11 ms 952 KB correct
27 Correct 9 ms 952 KB correct
28 Correct 5 ms 952 KB correct
29 Correct 3 ms 952 KB correct
30 Correct 9 ms 952 KB correct
31 Correct 10 ms 952 KB correct
32 Correct 10 ms 952 KB correct
33 Correct 9 ms 952 KB correct
34 Execution timed out 3056 ms 6184 KB Time limit exceeded
35 Halted 0 ms 0 KB -

Subtask #4
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 6184 KB correct
2 Correct 2 ms 6184 KB correct
3 Execution timed out 3038 ms 14684 KB Time limit exceeded
4 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB correct
2 Correct 3 ms 544 KB correct
3 Correct 3 ms 620 KB correct
4 Correct 3 ms 620 KB correct
5 Correct 2 ms 620 KB correct
6 Correct 2 ms 620 KB correct
7 Correct 2 ms 676 KB correct
8 Correct 2 ms 676 KB correct
9 Correct 2 ms 676 KB correct
10 Correct 2 ms 676 KB correct
11 Correct 3 ms 676 KB correct
12 Correct 2 ms 676 KB correct
13 Correct 2 ms 676 KB correct
14 Correct 26 ms 824 KB correct
15 Correct 13 ms 824 KB correct
16 Correct 15 ms 952 KB correct
17 Correct 20 ms 952 KB correct
18 Correct 5 ms 952 KB correct
19 Correct 23 ms 952 KB correct
20 Correct 12 ms 952 KB correct
21 Correct 14 ms 952 KB correct
22 Correct 10 ms 952 KB correct
23 Correct 8 ms 952 KB correct
24 Correct 10 ms 952 KB correct
25 Correct 3 ms 952 KB correct
26 Correct 11 ms 952 KB correct
27 Correct 9 ms 952 KB correct
28 Correct 5 ms 952 KB correct
29 Correct 3 ms 952 KB correct
30 Correct 9 ms 952 KB correct
31 Correct 10 ms 952 KB correct
32 Correct 10 ms 952 KB correct
33 Correct 9 ms 952 KB correct
34 Execution timed out 3056 ms 6184 KB Time limit exceeded
35 Halted 0 ms 0 KB -