oj.uz

Submission #641747

# Submission time Handle Problem Language Result Execution time Memory
641747 2022-09-17T14:21:13 Z jamezzz Thousands Islands (IOI22_islands) C++17
100 / 100
 238 ms 44168 KB 
#include "islands.h"
#include <bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#define dbg(...) printf(__VA_ARGS__);
#define getchar_unlocked getchar
#else
#define dbg(...)
#endif
#define sf scanf
#define pf printf
#define fi first
#define se second
#define pb push_back
#define psf push_front
#define ppb pop_back
#define ppf pop_front
#define sz(x) (int)x.size()
#define mnto(x,y) x=min(x,(__typeof__(x))y)
#define mxto(x,y) x=max(x,(__typeof__(x))y)
#define INF 1023456789
#define LINF 1023456789123456789
#define all(x) x.begin(),x.end()
#define lb(x,v) (lower_bound(all(x),v)-x.begin())
#define ub(x,v) (upper_bound(all(x),v)-x.begin())
#define disc(x) sort(all(x));x.resize(unique(all(x))-x.begin());
typedef long long ll;
typedef long double ld;
typedef pair<int,int> ii;
typedef pair<ll,ll> pll;
typedef tuple<int,int,int> iii;
typedef tuple<int,int,int,int> iiii;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<ii> vii;
mt19937 rng(time(0));

#define maxn 200005

int mxdep[maxn],pedge[maxn],par[maxn],dep[maxn];
bool vis[maxn],onstk[maxn],down[maxn],incycle[maxn],bothcycle[maxn];
map<int,ii> edgeid[maxn];
vi ans,cyclenode[2],tocycle[2],tocycleid[2],cycleid[2];;
vii AL[maxn];

void add(vector<int> &v){
	for(int x:v)ans.pb(x);
}

void addrev(vector<int> &v){
	for(int i=sz(v)-1;i>=0;--i)ans.pb(v[i]);
}

void dfs(int u){
	vis[u]=onstk[u]=true;
	mxdep[u]=-1;
	for(auto[v,i]:AL[u]){
		if(!vis[v]){
			pedge[v]=i;
			par[v]=u;
			dep[v]=dep[u]+1;
			dfs(v);
			down[i]=true;
		}
		if(onstk[v])mxto(mxdep[u],dep[v]);
		else{
			mxto(mxdep[u],mxdep[v]);
			down[i]=true;
		}
	}
	onstk[u]=false;
}

bool getcyc(int u,vi &nodes){
	vis[u]=onstk[u]=true;
	for(auto[v,i]:AL[u]){
		if(!vis[v]){
			if(getcyc(v,nodes)){
				nodes.pb(u);
				return true;
			}
		}
		if(onstk[v]){
			nodes.pb(v),nodes.pb(u);
			return true;
		}
	}
	onstk[u]=false;
	return false;
}

variant<bool,vi> find_journey(int N,int M,vi U,vi V){
	for(int i=0;i<M;++i){
		AL[U[i]].pb({V[i],i});
		if(edgeid[U[i]].find(V[i])==edgeid[U[i]].end())edgeid[U[i]][V[i]]={i,i};
		else edgeid[U[i]][V[i]].se=i;
	}
	dfs(0);
	for(int rt=0;rt<N;++rt){
		vi goodedge;
		for(auto[x,i]:AL[rt]){
			if(down[i]&&mxdep[x]>=dep[rt])goodedge.pb(x);
		}
		if(sz(goodedge)<2)continue;
		vi pathtort;
		int tmp=rt;
		while(tmp){
			pathtort.pb(pedge[tmp]);
			tmp=U[pedge[tmp]];
		}
		reverse(all(pathtort));
		add(pathtort);
		for(int i=0;i<2;++i){
			int x=goodedge[i];
			memset(vis,false,sizeof vis);
			memset(onstk,false,sizeof onstk);
			for(int x:pathtort)vis[U[x]]=vis[V[x]]=true;
			vis[rt]=onstk[rt]=true;
			vi nodes;
			getcyc(x,nodes);
			nodes.pb(rt);
			while(true){
				tocycle[i].pb(nodes.back());
				if(nodes.back()!=nodes[0])nodes.ppb();
				else break;
			}
			reverse(all(nodes));
			swap(nodes,cyclenode[i]);
		}
		
		int type=0;
		for(int i:cyclenode[0])incycle[i]=true;
		for(int i:cyclenode[1]){
			if(incycle[i]){
				bothcycle[i]=true;
				if(i!=rt)type=1;
			}
		}
		for(int x=0;x<2;++x){
			for(int i=0;i<sz(tocycle[x])-1;++i){
				int u=tocycle[x][i],v=tocycle[x][i+1];
				tocycleid[x].pb(edgeid[u][v].fi);
				swap(edgeid[u][v].fi,edgeid[u][v].se);
			}
			for(int i=0;i<sz(cyclenode[x])-1;++i){
				int u=cyclenode[x][i],v=cyclenode[x][i+1];
				cycleid[x].pb(edgeid[u][v].fi);
				swap(edgeid[u][v].fi,edgeid[u][v].se);
			}
		}
		if(type==0){//disjoint cycle
			for(int x=0;x<2;++x){
				add(tocycleid[x]);
				add(cycleid[x]);
				addrev(tocycleid[x]);
			}
			for(int x=0;x<2;++x){
				add(tocycleid[x]);
				addrev(cycleid[x]);
				addrev(tocycleid[x]);
			}
		}
		else{//overlapping cycle
			add(tocycleid[0]);
			add(cycleid[0]);
			addrev(tocycleid[0]);
			add(tocycleid[1]);
			vi added;
			for(int i:cycleid[1]){
				int u=U[i],v=V[i];
				if(u!=rt&&bothcycle[u]){
					int start=-1;
					for(int j=0;j<sz(cycleid[0]);++j){
						int id=cycleid[0][j];
						int u2=U[id],v2=V[id];
						if(v2==u)start=j;
					}
					for(int j=start;j>=0;--j)ans.pb(cycleid[0][j]);
					for(int j=sz(cycleid[0])-1;j>start;--j)ans.pb(cycleid[0][j]);
					break;
				}
				ans.pb(i);
				added.pb(i);
			}
			addrev(added);
			addrev(tocycleid[1]);
		}
		addrev(pathtort);
		return ans;
	}
	return false;
}

Compilation message

islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, vi, vi)':
islands.cpp:176:11: warning: unused variable 'u2' [-Wunused-variable]
  176 |       int u2=U[id],v2=V[id];
      |           ^~
islands.cpp:171:16: warning: unused variable 'v' [-Wunused-variable]
  171 |     int u=U[i],v=V[i];
      |                ^

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14420 KB Output is correct
2 Correct 8 ms 14804 KB Output is correct
3 Correct 8 ms 14420 KB Output is correct
4 Correct 7 ms 14420 KB Output is correct
5 Correct 9 ms 14436 KB Output is correct
6 Correct 10 ms 14784 KB Output is correct
7 Correct 55 ms 20644 KB Output is correct

Subtask #2
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14804 KB Output is correct
2 Correct 7 ms 14420 KB Output is correct
3 Correct 7 ms 14716 KB Output is correct
4 Correct 7 ms 14804 KB Output is correct
5 Correct 8 ms 14804 KB Output is correct
6 Correct 99 ms 29748 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 15164 KB Output is correct
2 Correct 8 ms 14420 KB Output is correct
3 Correct 9 ms 14436 KB Output is correct
4 Correct 8 ms 14804 KB Output is correct
5 Correct 9 ms 14676 KB Output is correct
6 Correct 8 ms 14788 KB Output is correct
7 Correct 8 ms 14408 KB Output is correct
8 Correct 8 ms 14848 KB Output is correct
9 Correct 7 ms 14804 KB Output is correct
10 Correct 9 ms 15104 KB Output is correct
11 Correct 7 ms 14804 KB Output is correct
12 Correct 9 ms 15060 KB Output is correct
13 Correct 8 ms 14344 KB Output is correct
14 Correct 8 ms 14420 KB Output is correct
15 Correct 8 ms 14768 KB Output is correct
16 Correct 7 ms 14420 KB Output is correct
17 Correct 59 ms 23620 KB Output is correct
18 Correct 45 ms 22404 KB Output is correct
19 Correct 8 ms 14420 KB Output is correct
20 Correct 7 ms 14804 KB Output is correct
21 Correct 7 ms 14764 KB Output is correct
22 Correct 7 ms 14804 KB Output is correct
23 Correct 102 ms 29248 KB Output is correct

Subtask #4
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 14928 KB Output is correct
2 Correct 9 ms 14992 KB Output is correct
3 Correct 64 ms 20404 KB Output is correct
4 Correct 65 ms 24644 KB Output is correct
5 Correct 9 ms 15040 KB Output is correct
6 Correct 11 ms 15088 KB Output is correct
7 Correct 9 ms 14804 KB Output is correct
8 Correct 8 ms 14804 KB Output is correct
9 Correct 9 ms 14788 KB Output is correct
10 Correct 9 ms 15064 KB Output is correct
11 Correct 9 ms 14676 KB Output is correct
12 Correct 9 ms 15092 KB Output is correct
13 Correct 10 ms 15212 KB Output is correct
14 Correct 9 ms 15080 KB Output is correct
15 Correct 9 ms 15192 KB Output is correct
16 Correct 9 ms 15060 KB Output is correct
17 Correct 8 ms 14420 KB Output is correct
18 Correct 9 ms 15060 KB Output is correct
19 Correct 9 ms 14932 KB Output is correct
20 Correct 64 ms 20400 KB Output is correct
21 Correct 99 ms 25548 KB Output is correct
22 Correct 8 ms 14548 KB Output is correct
23 Correct 8 ms 14412 KB Output is correct
24 Correct 7 ms 14420 KB Output is correct
25 Correct 8 ms 14832 KB Output is correct
26 Correct 9 ms 15048 KB Output is correct
27 Correct 67 ms 24488 KB Output is correct
28 Correct 78 ms 24732 KB Output is correct
29 Correct 8 ms 14420 KB Output is correct
30 Correct 93 ms 26756 KB Output is correct
31 Correct 8 ms 14804 KB Output is correct
32 Correct 70 ms 25112 KB Output is correct
33 Correct 61 ms 21088 KB Output is correct
34 Correct 41 ms 21104 KB Output is correct
35 Correct 9 ms 14948 KB Output is correct
36 Correct 70 ms 23920 KB Output is correct
37 Correct 74 ms 26544 KB Output is correct
38 Correct 8 ms 14576 KB Output is correct
39 Correct 63 ms 23128 KB Output is correct
40 Correct 9 ms 15092 KB Output is correct
41 Correct 80 ms 26608 KB Output is correct
42 Correct 78 ms 25224 KB Output is correct
43 Correct 10 ms 14420 KB Output is correct
44 Correct 9 ms 14692 KB Output is correct
45 Correct 9 ms 15060 KB Output is correct
46 Correct 34 ms 19916 KB Output is correct

Subtask #5
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14420 KB Output is correct
2 Correct 8 ms 14804 KB Output is correct
3 Correct 8 ms 14420 KB Output is correct
4 Correct 7 ms 14420 KB Output is correct
5 Correct 9 ms 14436 KB Output is correct
6 Correct 10 ms 14784 KB Output is correct
7 Correct 55 ms 20644 KB Output is correct
8 Correct 7 ms 14804 KB Output is correct
9 Correct 7 ms 14420 KB Output is correct
10 Correct 7 ms 14716 KB Output is correct
11 Correct 7 ms 14804 KB Output is correct
12 Correct 8 ms 14804 KB Output is correct
13 Correct 99 ms 29748 KB Output is correct
14 Correct 10 ms 15164 KB Output is correct
15 Correct 8 ms 14420 KB Output is correct
16 Correct 9 ms 14436 KB Output is correct
17 Correct 8 ms 14804 KB Output is correct
18 Correct 9 ms 14676 KB Output is correct
19 Correct 8 ms 14788 KB Output is correct
20 Correct 8 ms 14408 KB Output is correct
21 Correct 8 ms 14848 KB Output is correct
22 Correct 7 ms 14804 KB Output is correct
23 Correct 9 ms 15104 KB Output is correct
24 Correct 7 ms 14804 KB Output is correct
25 Correct 9 ms 15060 KB Output is correct
26 Correct 8 ms 14344 KB Output is correct
27 Correct 8 ms 14420 KB Output is correct
28 Correct 8 ms 14768 KB Output is correct
29 Correct 7 ms 14420 KB Output is correct
30 Correct 59 ms 23620 KB Output is correct
31 Correct 45 ms 22404 KB Output is correct
32 Correct 8 ms 14420 KB Output is correct
33 Correct 7 ms 14804 KB Output is correct
34 Correct 7 ms 14764 KB Output is correct
35 Correct 7 ms 14804 KB Output is correct
36 Correct 102 ms 29248 KB Output is correct
37 Correct 7 ms 14804 KB Output is correct
38 Correct 7 ms 14420 KB Output is correct
39 Correct 11 ms 14388 KB Output is correct
40 Correct 10 ms 14420 KB Output is correct
41 Correct 33 ms 17348 KB Output is correct
42 Correct 10 ms 14800 KB Output is correct
43 Correct 81 ms 29116 KB Output is correct
44 Correct 76 ms 27684 KB Output is correct
45 Correct 83 ms 29576 KB Output is correct
46 Correct 8 ms 14804 KB Output is correct
47 Correct 8 ms 14764 KB Output is correct
48 Correct 8 ms 14800 KB Output is correct
49 Correct 11 ms 15012 KB Output is correct
50 Correct 204 ms 40232 KB Output is correct
51 Correct 179 ms 41772 KB Output is correct
52 Correct 196 ms 42644 KB Output is correct
53 Correct 181 ms 44168 KB Output is correct
54 Correct 171 ms 40688 KB Output is correct
55 Correct 216 ms 41664 KB Output is correct
56 Correct 166 ms 41576 KB Output is correct
57 Correct 161 ms 35404 KB Output is correct
58 Correct 177 ms 35364 KB Output is correct
59 Correct 155 ms 35784 KB Output is correct
60 Correct 150 ms 36244 KB Output is correct
61 Correct 166 ms 34924 KB Output is correct
62 Correct 22 ms 17996 KB Output is correct
63 Correct 129 ms 33084 KB Output is correct
64 Correct 72 ms 23348 KB Output is correct
65 Correct 7 ms 14748 KB Output is correct
66 Correct 8 ms 14804 KB Output is correct
67 Correct 166 ms 38456 KB Output is correct
68 Correct 120 ms 30836 KB Output is correct
69 Correct 88 ms 28796 KB Output is correct
70 Correct 9 ms 15076 KB Output is correct
71 Correct 101 ms 29904 KB Output is correct
72 Correct 7 ms 14804 KB Output is correct
73 Correct 157 ms 35040 KB Output is correct
74 Correct 190 ms 38448 KB Output is correct
75 Correct 12 ms 15828 KB Output is correct
76 Correct 56 ms 25184 KB Output is correct
77 Correct 86 ms 35272 KB Output is correct
78 Correct 147 ms 35844 KB Output is correct
79 Correct 7 ms 14804 KB Output is correct
80 Correct 238 ms 42636 KB Output is correct
81 Correct 9 ms 14932 KB Output is correct
82 Correct 44 ms 19716 KB Output is correct
83 Correct 8 ms 14932 KB Output is correct
84 Correct 8 ms 14828 KB Output is correct
85 Correct 57 ms 24900 KB Output is correct
86 Correct 10 ms 15060 KB Output is correct
87 Correct 9 ms 14664 KB Output is correct
88 Correct 11 ms 15316 KB Output is correct
89 Correct 141 ms 36300 KB Output is correct
90 Correct 141 ms 34832 KB Output is correct
91 Correct 212 ms 41440 KB Output is correct
92 Correct 8 ms 14804 KB Output is correct