Submission #300906

# Submission time Handle Problem Language Result Execution time Memory
300906 2020-09-17T14:59:42 Z gs14004 Comparing Plants (IOI20_plants) C++17
Compilation error
0 ms 0 KB
#include "plants.h"
#include <bits/stdc++.h>
#define sz(v) ((int)(v).size())
#define all(v) (v).begin(), (v).end()
#define rank fuck
using namespace std;
using lint = long long;
using llf = long double;
using pi = pair<lint, lint>;
const int MAXN = 200005;
const int MAXT = 2100005;

int n, rank[MAXN];
lint DL[18][MAXN], DR[18][MAXN];
int L[18][MAXN], R[18][MAXN];
vector<int> lev[MAXN];

struct node{
	int minv;
	int lidx, ridx;
	node(){
		minv = 1e9;
	}
	node(int x, int v){
		lidx = ridx = x;
		minv = v;
	}
	node operator+(const node &n)const{
		node x = *this;
		node y = n;
		if(x.minv < y.minv) return x;
		if(x.minv > y.minv) return y;
		x.lidx = min(x.lidx, y.lidx);
		x.ridx = max(x.ridx, y.ridx);
		return x;
	}
};

struct seg{
	node tree[MAXT];
	int lim;
	void init(int n){
		for(lim = 1; lim <= 3 * n; lim <<= 1);
		for(int i=0; i<3*n; i++) tree[i + lim] = node(i-n, 1e9);
		for(int i=lim-1; i; i--) tree[i] = tree[2*i] + tree[2*i+1];
	}
	void upd(int x, int v){
		node val(x, v);
		x += n + lim;
		tree[x] = val;
		while(x > 1){
			x >>= 1;
			tree[x] = tree[2*x] + tree[2*x+1];
		}
	}
	node query(int s, int e){
		s += lim + n;
		e += lim + n;
		node ret;
		while(s < e){
			if(s%2 == 1) ret = ret + tree[s++];
			if(e%2 == 0) ret = ret + tree[e--];
			s >>= 1;
			e >>= 1;
		}
		if(s == e) ret = ret + tree[s];
		return ret;
	}
}seg;

void init(int k, std::vector<int> r) {
	n = sz(r);
	if(k * 2 > n) k = n;
	if(n > 300) return 0;
	int layer = 0;
	while(count(rank, rank + n, 0)){
		vector<int> vect;
		for(int j=0; j<n; j++){
			if(r[j] || rank[j]) continue;
			bool claim = true;
			for(int x=1; x<=k-1; x++){
				if(r[(j-x+n)%n] == 0) claim = false;
			}
			if(claim) vect.push_back(j);
		}
		layer++;
		for(auto &j : vect) rank[j] = layer;
		for(auto &j : vect){
			r[j] = k - 1;
			for(int x=1; x<=k-1; x++){
				r[(j-x+n)%n]--;
			}
		}
	}
	for(int i=0; i<n; i++){
		lev[rank[i]].push_back(i);
	}
	seg.init(n);
	for(int i=layer; i; i--){
		for(auto &j : lev[i]){
			auto qr = seg.query(j-k+1, j+k-1);
			L[0][j] = R[0][j] = j;
			if(qr.minv > 1e8) continue;
			if(qr.lidx < j) L[0][j] = (qr.lidx + n) % n;
			if(qr.ridx > j) R[0][j] = (qr.ridx + n) % n;
			DL[0][j] = (j - L[0][j] + n) % n;
			DR[0][j] = (R[0][j] - j + n) % n;
		}
		for(auto &j : lev[i]){
			seg.upd(j - n, i);
			seg.upd(j    , i);
			seg.upd(j + n, i);
		}
	}
	for(int i=1; i<18; i++){
		for(int j=0; j<n; j++){
			L[i][j] = L[i-1][L[i-1][j]];
			R[i][j] = R[i-1][R[i-1][j]];
			DL[i][j] = DL[i-1][j] + DL[i-1][L[i-1][j]];
			DR[i][j] = DR[i-1][j] + DR[i-1][R[i-1][j]];
		}
	}
}

int compare_plants(int x, int y) {
	if(rank[x] == rank[y]) return 0;
	if(rank[x] > rank[y]) return -compare_plants(y, x);
	lint st = x, ed = x;
	{
		lint dist = 0;
		int p = x;
		for(int i=17; i>=0; i--){
			if(rank[L[i][p]] <= rank[y]){
				dist += DL[i][p];
				p = L[i][p];
			}
		}
		st = x - dist;
	}
	{
		lint dist = 0;
		int p = x;
		for(int i=17; i>=0; i--){
			if(rank[R[i][p]] <= rank[y]){
				dist += DR[i][p];
				p = R[i][p];
			}
		}
		ed = x + dist;
	}
	lint Q = ed - ed % n + y;
	if(Q > ed) Q -= n;
	return Q >= st;
}

Compilation message

plants.cpp: In function 'void init(int, std::vector<int>)':
plants.cpp:74:21: error: return-statement with a value, in function returning 'void' [-fpermissive]
   74 |  if(n > 300) return 0;
      |                     ^