Submission #354255

#	Time	Username	Problem	Language	Result	Execution time	Memory
354255		ryansee	Comparing Plants (IOI20_plants)	C++14	0 / 100	4041 ms	107624 KiB

plants

#include "plants.h"
 
#include "bits/stdc++.h"
using namespace std;
 
#define FAST ios_base::sync_with_stdio(false); cin.tie(0);
#define pb push_back
#define eb emplace_back
#define ins insert
#define f first
#define s second
#define cbr cerr<<"hi\n"
#define mmst(x, v) memset((x), v, sizeof ((x)))
#define siz(x) ll(x.size())
#define all(x) (x).begin(), (x).end()
#define lbd(x,y) (lower_bound(all(x),y)-x.begin())
#define ubd(x,y) (upper_bound(all(x),y)-x.begin())
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());    //can be used by calling rng() or shuffle(A, A+n, rng)
inline long long rand(long long x, long long y) { return rng() % (y+1-x) + x; } //inclusivesss
string inline to_string(char c) {string s(1,c);return s;} template<typename T> inline T gcd(T a,T b){ return a==0?llabs(b):gcd(b%a,a); }
 
using ll=long long; 
using ld=long double;
#define FOR(i,s,e) for(ll i=s;i<=ll(e);++i)
#define DEC(i,s,e) for(ll i=s;i>=ll(e);--i)
using pi=pair<ll,ll>; using spi=pair<ll,pi>; using dpi=pair<pi,pi>; 
 
long long LLINF = 1e18;
int INF = 1e9+1e6;
#define MAXN (5002)
 
int n, start;
ll A[MAXN];
bitset<MAXN> gone, done;
inline ll cy(ll x) {
	x %= n, x += n, x %= n; return x;
}
vector<int> v[MAXN];
bitset<MAXN> reach[MAXN];
void init(int k, std::vector<int> r) {
	n=r.size(); if(n > 5000) return; vector<int> o=r;
	function<void(int,int)> zero=[&](int x,int op){
		FOR(j,x+1,x+k-1) if(!gone[cy(j)]) {
			if(r[cy(j)]==0) assert(op==1), zero(cy(j), -1);
			r[cy(j)] += op;
			if(r[cy(j)]==0) assert(op==-1), zero(cy(j), 1);
		}
	};
	FOR(i,0,n-1) {
		DEC(j,i-1,i-k+1) {
			if(r[cy(j)]==0) goto bad;
		}
		start = i;
		break;
		bad:;
	}
	DEC(i,start-1,start-n) if(r[cy(i)]==0) {
		zero(cy(i), 1);
	}
	// FOR(i,0,n-1) cerr<<o[i]<<' '; cerr<<'\n';
	// FOR(i,0,n-1) cerr<<r[i]<<' '; cerr<<'\n';
	while(1) {
		start = -1;
		FOR(i,0,n-1) if(!gone[i] && r[i] == 0) { start = i; break; }
		if(start == -1) break;
		gone[start]=1, zero(start, -1);
		FOR(i,start+1,start+k-1) if(!gone[cy(i)]) {
			A[cy(i)]=max(A[cy(i)], A[start]+1);
		}
		DEC(i,start-1,start-k+1) if(!gone[cy(i)]) {
			A[cy(i)] = max(A[cy(i)], A[start]+1);
			-- r[cy(i)];
			if(r[cy(i)]==0) zero(cy(i), 1);
		}
	}
	FOR(i,0,n-1) assert(r[i]==0);
	FOR(i,0,n-1) FOR(jj,i+1,i+k-1) { int j=cy(jj);
		assert(A[i] ^ A[j]);
		if(A[i] < A[j]) v[i].eb(j);
		else v[j].eb(i);
	}
	function<void(ll,ll)>dfs=[&](ll x,ll o){
		if(reach[o][x]) return;
		reach[o][x]=1;
		for(auto i:v[x]) dfs(i, o);
	};
	FOR(i,0,n-1) dfs(i, i);
}
int compare_plants(int x, int y) {
	if(n > 5000) return 0;
	if(reach[x][y] || reach[y][x]) return A[x] < A[y] ? 1 : -1;
	else return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 14
• Subtask 3: 0 / 13
• Subtask 4: 0 / 17
• Subtask 5: 0 / 11
• Subtask 6: 0 / 15
• Subtask 7: 0 / 25