oj.uz

Submission #1052822

# Submission time Handle Problem Language Result Execution time Memory
1052822 2024-08-11T02:09:37 Z pcc Simurgh (IOI17_simurgh) C++17
100 / 100
 145 ms 9176 KB 
#include "simurgh.h"
#include <bits/stdc++.h>
using namespace std;

#define pii pair<int,int>
#define fs first
#define sc second

const int mxn = 550;
int N;
pii par[mxn];
vector<pii> paths[mxn];
vector<pii> tree[mxn];
vector<int> back_edge;
int tp[mxn*mxn];
vector<pii> edges;
int dep[mxn];
vector<int> tree_edge;
set<int> tree_st;
int normal = 0;

/*
std::vector<int> r(n - 1);
for(int i = 0; i < n - 1; i++)
	r[i] = i;
int common = count_common_roads(r);
if(common == n - 1)
	return r;
r[0] = n - 1;
return r;
*/

struct DSU{
	int dsu[mxn],sz[mxn];
	DSU(){
		iota(dsu,dsu+mxn,0);
		fill(sz,sz+mxn,1);
	}
	void init(){
		iota(dsu,dsu+mxn,0);
		fill(sz,sz+mxn,1);
	}
	int root(int k){
		return k == dsu[k]?k:dsu[k] = root(dsu[k]);
	}
	void onion(int a,int b){
		a = root(a),b = root(b);
		if(a == b)return;
		if(sz[a]<sz[b])swap(a,b);
		sz[a] += sz[b];
		dsu[b] = a;
	}
};
DSU dsu;

void dfs(int now,int fa){
	for(auto &[nxt,id]:paths[now]){
		if(nxt == fa)continue;
		if(par[nxt].fs == -1){
			tree_edge.push_back(id);
			par[nxt] = pii(now,id);
			dep[nxt] = dep[now]+1;
			dfs(nxt,now);
		}
		else{
			back_edge.push_back(id);
		}
	}
	return;
}

int C = 0;

int ask(vector<int> &v){
	C++;
	assert(C<=30000);
	int re = count_common_roads(v);
	return re;
}

int ask(set<int> &st){
	vector<int> v;
	for(auto &i:st)v.push_back(i);
	return ask(v);
}

void solve_cycle(vector<int> &v,int eid){
	vector<int> res;
	auto st = tree_st;
	st.insert(eid);
	for(auto &i:v){
		st.erase(i);
		res.push_back(ask(st));
		st.insert(i);
	}
	st.erase(eid);
	int mn = *min_element(res.begin(),res.end());
	int mx = *max_element(res.begin(),res.end());
	//cerr<<"CYCLE: "<<mx<<' '<<mn<<endl;for(auto &i:v)cerr<<i<<',';cerr<<endl;for(auto &i:res)cerr<<i<<',';cerr<<endl;
	if(mn == mx){
		if(normal == mn){
			tp[eid] = 0;
			for(auto &i:v)tp[i] = 0;
		}
		else if(normal<mn){
			tp[eid] = 1;
			for(auto &i:v)tp[i] = 0;
		}
		else if(normal>mn){
			tp[eid] = 0;
			for(auto &i:v)tp[i] = 1;
		}
	}
	else{
		assert(mx-mn == 1);
		if(mx>normal)tp[eid] = 1;
		else tp[eid] = 0;
		for(int i = 0;i<v.size();i++){
			if(res[i] == mx)tp[v[i]] = 0;
			else tp[v[i]] = 1;
		}
	}
	return;
}

void solve(int eid){
	auto [a,b] = edges[eid];
	if(dep[a]>dep[b])swap(a,b);
	int tmp = b;
	vector<int> v;
	while(tmp != a){
		v.push_back(par[tmp].sc);
		tmp = par[tmp].fs;
		//cerr<<v.back()<<','<<tmp<<' '<<a<<endl;
	}
	//cerr<<"SOLVE: "<<eid<<"::";for(auto &i:v)cerr<<i<<',';cerr<<endl;
	int checker = -1;
	bool done = true;
	for(auto &i:v){
		if(tp[i] == -1)done = false;
		if(tp[i] != -1)checker = i;
	}
	if(done)return;
	if(checker == -1)solve_cycle(v,eid);
	else{
		auto st = tree_st;
		st.erase(checker);
		st.insert(eid);
		int re = ask(st);
		if(re == normal)tp[eid] = tp[checker];
		else tp[eid] = tp[checker]^1;
		st.erase(eid);
		st.insert(checker);
		//cerr<<"CHECKER: "<<checker<<','<<re<<endl;
		for(auto &i:v){
			if(tp[i] == -1){
				auto [a,b] = edges[i];
				st.erase(i);
				st.insert(eid);
				//cerr<<i<<"::";for(auto &j:st)cerr<<j<<',';cerr<<ask(st)<<endl;
				if(ask(st) == normal)tp[i] = tp[eid];
				else tp[i] = tp[eid]^1;
				st.insert(i);
				st.erase(eid);
			}
		}
	}
	//cerr<<"EDGES: ";for(int i = 0;i<edges.size();i++)cerr<<tp[i]<<' ';cerr<<endl;
	return;
}

int get_num(vector<int> &tar){
	dsu.init();
	vector<int> v;
	for(auto &i:tar){
		auto [a,b] = edges[i];
		if(dsu.root(a) == dsu.root(b)){
			cerr<<"WA: not forest!"<<endl;
			assert(false);
		}
		dsu.onion(a,b);
		v.push_back(i);
	}
	int s = 0;
	for(auto &i:tree_edge){
		if(tp[i] == -1){
			cerr<<"WA tree not known!"<<endl;
			assert(false);
		}
		auto [a,b] = edges[i];
		if(dsu.root(a) == dsu.root(b))continue;
		dsu.onion(a,b);
		v.push_back(i);
		s += tp[i];
	}
	if(v.size() != N-1){
		cerr<<"WA: not asking a tree!"<<endl;
		cerr<<v.size()<<endl;
		assert(false);
	}
	int re = ask(v);
	return re-s;
}

void dc(vector<int> edges,int cnt){
	if(!cnt||edges.empty())return;
	if(cnt == edges.size()){
		for(auto &i:edges){
			tp[i] = 1;
		}
		return;
	}
	vector<int> lv,rv;
	int mid = edges.size()>>1;
	for(int i = 0;i<edges.size();i++){
		if(i<mid)lv.push_back(edges[i]);
		else rv.push_back(edges[i]);
	}
	int lc = get_num(lv),rc = cnt-lc;
	dc(lv,lc);dc(rv,rc);
}

void calc(int now){
	vector<int> edges;
	for(auto [_,id]:paths[now]){
		if(tp[id] == -1)edges.push_back(id);
	}
	dc(edges,get_num(edges));
	for(auto &i:edges){
		if(tp[i] == -1)tp[i] = 0;
	}
	return;
}

std::vector<int> find_roads(int n, std::vector<int> u, std::vector<int> v) {
	N = n;
	memset(tp,-1,sizeof(tp));
	for(auto &i:par)i = pii(-1,-1);
	for(int i = 0;i<u.size();i++){
		int a = u[i],b = v[i];
		edges.push_back(pii(a,b));
		paths[a].push_back(pii(b,i));
		paths[b].push_back(pii(a,i));
	}
	par[0] = pii(0,-1);
	dfs(0,0);
	sort(back_edge.begin(),back_edge.end());
	back_edge.resize(unique(back_edge.begin(),back_edge.end())-back_edge.begin());
	for(auto &i:tree_edge)tree_st.insert(i);
	//cerr<<"TREE :";for(auto &i:tree_edge)cerr<<i<<',';cerr<<endl;
	normal = ask(tree_edge);
	//cerr<<"NORMAL: "<<normal<<endl;
	for(auto &i:back_edge)solve(i);
	for(auto &i:tree_edge){
		if(tp[i] == -1)tp[i] = 1;
	}
	for(int i = 0;i<N;i++){
		calc(i);
	}
	vector<int> ans;
	for(int i = 0;i<edges.size();i++)if(tp[i] != 0)ans.push_back(i);
	//cerr<<C<<" ASKS"<<endl;
	//cerr<<"ANS: ";for(auto &i:ans)cerr<<i<<',';cerr<<endl;
	return ans;
}

Compilation message

simurgh.cpp: In function 'void solve_cycle(std::vector<int>&, int)':
simurgh.cpp:118:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  118 |   for(int i = 0;i<v.size();i++){
      |                 ~^~~~~~~~~
simurgh.cpp: In function 'void solve(int)':
simurgh.cpp:157:10: warning: structured binding declaration set but not used [-Wunused-but-set-variable]
  157 |     auto [a,b] = edges[i];
      |          ^~~~~
simurgh.cpp: In function 'int get_num(std::vector<int>&)':
simurgh.cpp:196:14: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  196 |  if(v.size() != N-1){
      |     ~~~~~~~~~^~~~~~
simurgh.cpp: In function 'void dc(std::vector<int>, int)':
simurgh.cpp:207:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  207 |  if(cnt == edges.size()){
      |     ~~~~^~~~~~~~~~~~~~~
simurgh.cpp:215:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  215 |  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:239:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  239 |  for(int i = 0;i<u.size();i++){
      |                ~^~~~~~~~~
simurgh.cpp:261:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  261 |  for(int i = 0;i<edges.size();i++)if(tp[i] != 0)ans.push_back(i);
      |                ~^~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1880 KB correct
2 Correct 1 ms 1628 KB correct
3 Correct 1 ms 1628 KB correct
4 Correct 1 ms 1628 KB correct
5 Correct 1 ms 1628 KB correct
6 Correct 1 ms 1628 KB correct
7 Correct 1 ms 1628 KB correct
8 Correct 1 ms 1628 KB correct
9 Correct 0 ms 1504 KB correct
10 Correct 1 ms 1628 KB correct
11 Correct 0 ms 1628 KB correct
12 Correct 0 ms 1628 KB correct
13 Correct 0 ms 1628 KB correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1880 KB correct
2 Correct 1 ms 1628 KB correct
3 Correct 1 ms 1628 KB correct
4 Correct 1 ms 1628 KB correct
5 Correct 1 ms 1628 KB correct
6 Correct 1 ms 1628 KB correct
7 Correct 1 ms 1628 KB correct
8 Correct 1 ms 1628 KB correct
9 Correct 0 ms 1504 KB correct
10 Correct 1 ms 1628 KB correct
11 Correct 0 ms 1628 KB correct
12 Correct 0 ms 1628 KB correct
13 Correct 0 ms 1628 KB correct
14 Correct 1 ms 1628 KB correct
15 Correct 1 ms 1628 KB correct
16 Correct 1 ms 1628 KB correct
17 Correct 1 ms 1564 KB correct
18 Correct 1 ms 1628 KB correct
19 Correct 1 ms 1628 KB correct
20 Correct 1 ms 1628 KB correct
21 Correct 1 ms 1628 KB correct
22 Correct 1 ms 1628 KB correct
23 Correct 1 ms 1628 KB correct
24 Correct 1 ms 1628 KB correct
25 Correct 1 ms 1628 KB correct
26 Correct 1 ms 1628 KB correct
27 Correct 1 ms 1628 KB correct
28 Correct 1 ms 1628 KB correct
29 Correct 1 ms 1628 KB correct
30 Correct 1 ms 1644 KB correct
31 Correct 1 ms 1628 KB correct
32 Correct 1 ms 1628 KB correct
33 Correct 1 ms 1628 KB correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1880 KB correct
2 Correct 1 ms 1628 KB correct
3 Correct 1 ms 1628 KB correct
4 Correct 1 ms 1628 KB correct
5 Correct 1 ms 1628 KB correct
6 Correct 1 ms 1628 KB correct
7 Correct 1 ms 1628 KB correct
8 Correct 1 ms 1628 KB correct
9 Correct 0 ms 1504 KB correct
10 Correct 1 ms 1628 KB correct
11 Correct 0 ms 1628 KB correct
12 Correct 0 ms 1628 KB correct
13 Correct 0 ms 1628 KB correct
14 Correct 1 ms 1628 KB correct
15 Correct 1 ms 1628 KB correct
16 Correct 1 ms 1628 KB correct
17 Correct 1 ms 1564 KB correct
18 Correct 1 ms 1628 KB correct
19 Correct 1 ms 1628 KB correct
20 Correct 1 ms 1628 KB correct
21 Correct 1 ms 1628 KB correct
22 Correct 1 ms 1628 KB correct
23 Correct 1 ms 1628 KB correct
24 Correct 1 ms 1628 KB correct
25 Correct 1 ms 1628 KB correct
26 Correct 1 ms 1628 KB correct
27 Correct 1 ms 1628 KB correct
28 Correct 1 ms 1628 KB correct
29 Correct 1 ms 1628 KB correct
30 Correct 1 ms 1644 KB correct
31 Correct 1 ms 1628 KB correct
32 Correct 1 ms 1628 KB correct
33 Correct 1 ms 1628 KB correct
34 Correct 25 ms 3544 KB correct
35 Correct 25 ms 3544 KB correct
36 Correct 21 ms 3032 KB correct
37 Correct 5 ms 1628 KB correct
38 Correct 26 ms 3584 KB correct
39 Correct 22 ms 3288 KB correct
40 Correct 18 ms 3032 KB correct
41 Correct 26 ms 3540 KB correct
42 Correct 25 ms 3540 KB correct
43 Correct 11 ms 2764 KB correct
44 Correct 10 ms 2396 KB correct
45 Correct 10 ms 2652 KB correct
46 Correct 8 ms 2396 KB correct
47 Correct 5 ms 1884 KB correct
48 Correct 3 ms 1508 KB correct
49 Correct 4 ms 1624 KB correct
50 Correct 5 ms 1884 KB correct
51 Correct 11 ms 2652 KB correct
52 Correct 9 ms 2396 KB correct
53 Correct 10 ms 2396 KB correct
54 Correct 12 ms 2876 KB correct
55 Correct 12 ms 2648 KB correct
56 Correct 12 ms 2652 KB correct
57 Correct 11 ms 2652 KB correct

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1624 KB correct
2 Correct 1 ms 1624 KB correct
3 Correct 83 ms 7332 KB correct
4 Correct 136 ms 9176 KB correct
5 Correct 139 ms 9168 KB correct
6 Correct 135 ms 9160 KB correct
7 Correct 119 ms 9168 KB correct
8 Correct 120 ms 9168 KB correct
9 Correct 137 ms 9012 KB correct
10 Correct 139 ms 9056 KB correct
11 Correct 138 ms 9168 KB correct
12 Correct 141 ms 9168 KB correct
13 Correct 1 ms 1624 KB correct
14 Correct 138 ms 9168 KB correct
15 Correct 140 ms 9092 KB correct

Subtask #5
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1880 KB correct
2 Correct 1 ms 1628 KB correct
3 Correct 1 ms 1628 KB correct
4 Correct 1 ms 1628 KB correct
5 Correct 1 ms 1628 KB correct
6 Correct 1 ms 1628 KB correct
7 Correct 1 ms 1628 KB correct
8 Correct 1 ms 1628 KB correct
9 Correct 0 ms 1504 KB correct
10 Correct 1 ms 1628 KB correct
11 Correct 0 ms 1628 KB correct
12 Correct 0 ms 1628 KB correct
13 Correct 0 ms 1628 KB correct
14 Correct 1 ms 1628 KB correct
15 Correct 1 ms 1628 KB correct
16 Correct 1 ms 1628 KB correct
17 Correct 1 ms 1564 KB correct
18 Correct 1 ms 1628 KB correct
19 Correct 1 ms 1628 KB correct
20 Correct 1 ms 1628 KB correct
21 Correct 1 ms 1628 KB correct
22 Correct 1 ms 1628 KB correct
23 Correct 1 ms 1628 KB correct
24 Correct 1 ms 1628 KB correct
25 Correct 1 ms 1628 KB correct
26 Correct 1 ms 1628 KB correct
27 Correct 1 ms 1628 KB correct
28 Correct 1 ms 1628 KB correct
29 Correct 1 ms 1628 KB correct
30 Correct 1 ms 1644 KB correct
31 Correct 1 ms 1628 KB correct
32 Correct 1 ms 1628 KB correct
33 Correct 1 ms 1628 KB correct
34 Correct 25 ms 3544 KB correct
35 Correct 25 ms 3544 KB correct
36 Correct 21 ms 3032 KB correct
37 Correct 5 ms 1628 KB correct
38 Correct 26 ms 3584 KB correct
39 Correct 22 ms 3288 KB correct
40 Correct 18 ms 3032 KB correct
41 Correct 26 ms 3540 KB correct
42 Correct 25 ms 3540 KB correct
43 Correct 11 ms 2764 KB correct
44 Correct 10 ms 2396 KB correct
45 Correct 10 ms 2652 KB correct
46 Correct 8 ms 2396 KB correct
47 Correct 5 ms 1884 KB correct
48 Correct 3 ms 1508 KB correct
49 Correct 4 ms 1624 KB correct
50 Correct 5 ms 1884 KB correct
51 Correct 11 ms 2652 KB correct
52 Correct 9 ms 2396 KB correct
53 Correct 10 ms 2396 KB correct
54 Correct 12 ms 2876 KB correct
55 Correct 12 ms 2648 KB correct
56 Correct 12 ms 2652 KB correct
57 Correct 11 ms 2652 KB correct
58 Correct 1 ms 1624 KB correct
59 Correct 1 ms 1624 KB correct
60 Correct 83 ms 7332 KB correct
61 Correct 136 ms 9176 KB correct
62 Correct 139 ms 9168 KB correct
63 Correct 135 ms 9160 KB correct
64 Correct 119 ms 9168 KB correct
65 Correct 120 ms 9168 KB correct
66 Correct 137 ms 9012 KB correct
67 Correct 139 ms 9056 KB correct
68 Correct 138 ms 9168 KB correct
69 Correct 141 ms 9168 KB correct
70 Correct 1 ms 1624 KB correct
71 Correct 138 ms 9168 KB correct
72 Correct 140 ms 9092 KB correct
73 Correct 1 ms 1628 KB correct
74 Correct 145 ms 9148 KB correct
75 Correct 135 ms 9164 KB correct
76 Correct 58 ms 4560 KB correct
77 Correct 138 ms 9168 KB correct
78 Correct 141 ms 9156 KB correct
79 Correct 140 ms 9164 KB correct
80 Correct 137 ms 9164 KB correct
81 Correct 106 ms 8656 KB correct
82 Correct 135 ms 9168 KB correct
83 Correct 86 ms 5588 KB correct
84 Correct 61 ms 7116 KB correct
85 Correct 56 ms 6196 KB correct
86 Correct 38 ms 4820 KB correct
87 Correct 30 ms 4056 KB correct
88 Correct 25 ms 3284 KB correct
89 Correct 26 ms 3288 KB correct
90 Correct 22 ms 3136 KB correct
91 Correct 11 ms 1876 KB correct
92 Correct 10 ms 1628 KB correct
93 Correct 53 ms 6224 KB correct
94 Correct 38 ms 4816 KB correct
95 Correct 38 ms 4820 KB correct
96 Correct 24 ms 3288 KB correct
97 Correct 28 ms 3288 KB correct
98 Correct 30 ms 4056 KB correct
99 Correct 26 ms 3288 KB correct
100 Correct 14 ms 2136 KB correct
101 Correct 12 ms 1624 KB correct
102 Correct 62 ms 5588 KB correct
103 Correct 63 ms 5588 KB correct
104 Correct 61 ms 5372 KB correct
105 Correct 62 ms 5332 KB correct