Submission #348317

#	Time	Username	Problem	Language	Result	Execution time	Memory
348317		amunduzbaev	Tropical Garden (IOI11_garden)	C++14	100 / 100	2835 ms	52320 KiB

garden

/** made by amunduzbaev **/
 
#include "garden.h"
#include "gardenlib.h"
//#include "grader.cpp"
#include <bits/stdc++.h>
using namespace std;
 
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define fastios ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define Pi acos(-1);
#define mod 1e9+7
#define inf 1e18
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii; 
typedef pair<ll, ll> pll; 
typedef vector<ll> vll;
typedef vector<int> vii;
typedef vector<pll> vpll;
typedef vector<pii> vpii;
template<class T> bool umin(T& a, const T& b) {return a > b? a = b, true:false;}
template<class T> bool umax(T& a, const T& b) {return a < b? a = b, true:false;}
int msb(int val){return sizeof(int)*8-__builtin_clzll(val)-1;}
 
const int NN = 3e5+5;
 
vii edges[NN], gg[NN];
vii cyc;
stack<int> ss;
int goal, oncyc[NN], last, used[NN], len[NN], in[NN]; 
int comp[NN], pos[NN], bup[NN], ddn[NN];
 
void dfs(int u){
	if(used[u] && in[u]){
		oncyc[u] = ++last;
		cyc.pb(u);
		int tmp = 0;
		while(!ss.empty() && ss.top() != u){
			oncyc[ss.top()] = last;
			pos[ss.top()] = ++tmp;
			cyc.pb(ss.top());
			ss.pop();
		}
		len[last] = sz(cyc);
		return;
	}
	if(used[u]) return;
	
	used[u] = 1;
	ss.push(u);
	in[u] = 1;
	
	dfs(bup[u]);
	
	in[u] = 0;
	if(!ss.empty()) ss.pop();
}
 
int tin[NN], tout[NN], tim;
int rr[NN], dd[NN], ddr[NN];
 
void treepr(int u, int root){
	comp[u] = comp[root];
	rr[u] = root;
	tin[u] = ++tim;
	for(auto x:edges[u]){
		if(oncyc[x]) continue;
		ddr[x] = ddr[u]+1;
		treepr(x, root);
	}
	tout[u] = tim;
}
 
bool check(int u, int k, int goal){
	if(comp[u] != comp[goal]) return 0;
	if(oncyc[u] && !oncyc[goal]) return 0;
	
	else if(oncyc[u] && oncyc[goal]){
		k %= len[oncyc[u]];
		return (dd[u] == k);
	}
	
	else if(!oncyc[u] && oncyc[goal]){
		k = k - ddr[u] - dd[rr[u]];
		if(k < 0) return 0;
		return (k % len[oncyc[rr[u]]] == 0);
	}
	
	else if(!oncyc[u] && !oncyc[goal]){
		if(tin[goal] <= tin[u] && tout[goal] >= tout[u]) 
			return (ddr[u] - ddr[goal] == k);
	}
	
	return 0;
}

bool ncheck(int u, int k, int goal){
	if(comp[u] != comp[goal]) return 0;
	if(oncyc[u] && !oncyc[goal]) return 0;
	
	else if(oncyc[u] && oncyc[goal]){
		k %= len[oncyc[u]];
		return (ddn[u] == k);
	}
	
	else if(!oncyc[u] && oncyc[goal]){
		k = k - ddr[u] - ddn[rr[u]];
		if(k < 0) return 0;
		return (k % len[oncyc[rr[u]]] == 0);
	}
	
	else if(!oncyc[u] && !oncyc[goal]){
		if(tin[goal] <= tin[u] && tout[goal] >= tout[u]) 
			return (ddr[u] - ddr[goal] == k);
	}
	
	return 0;
}

 
 
 
void count_routes(int n, int m, int p, int R[][2], int q, int kk[]){
	for(int i=0; i<m; i++){
		int a = R[i][0], b = R[i][1];
		if(sz(gg[a]) < 2) gg[a].pb(b);
		if(sz(gg[b]) < 2) gg[b].pb(a);
	}
	
	memset(rr, -1, sizeof rr);
	memset(bup, -1, sizeof bup);
	memset(dd, -1, sizeof dd);
	memset(ddn, -1, sizeof ddn);
	
	for(int i=0;i<n;i++){
		for(int j=0;j<sz(gg[i]);j++){
			int to = gg[i][j];
			if(gg[to][0] == i && sz(gg[to]) > 1){
				bup[i + j * n] = to+n;
				edges[to+n].pb(i + j*n);
			}else{
				bup[i + j * n] = to;
				edges[to].pb(i + j*n);
			}
		}
	}
	
	goal = p;
	
	for(int i=0;i<2*n;i++){
		if(used[i]) continue;
		while(!ss.empty()) ss.pop();
		cyc.clear();
		dfs(i);
		for(auto x:cyc){
			ddr[x] = 0, comp[x] = oncyc[x];
			treepr(x, x);
		}
	}
	
	if(oncyc[p]){
		int cur = p, dis = 0;
		while(cur != p || dis == 0){
			dd[cur] = (len[oncyc[cur]] - dis), dis++;
			cur = bup[cur];
		}dd[p] = 0;
	}
	
	if(oncyc[p+n]){
		int cur = p+n, dis = 0;
		while(cur != p+n || dis == 0){
			ddn[cur] = (len[oncyc[cur]] - dis), dis++;
			cur = bup[cur];
		}ddn[p+n] = 0;
	}
	
	for(int i=0;i<q;i++){
		int cnt = 0;
		for(int j=0;j<n;j++) cnt += ( check(j, kk[i], p) | ncheck(j, kk[i], p+n) );
		
		answer(cnt);
	}
}
 
/*
 
6 6 0
1 2
0 1
0 3
3 4
4 5
1 5
1
3
2
 
5 5 2
1 0
1 2
3 2
1 3
4 2
2
3 1
1 2
 
*/

• Subtask 1: 49 / 49
• Subtask 2: 20 / 20
• Subtask 3: 31 / 31