Submission #735235

#	Time	Username	Problem	Language	Result	Execution time	Memory
735235		myrcella	Rail (IOI14_rail)	C++17	100 / 100	87 ms	4556 KiB

rail

//by szh
#include<bits/stdc++.h>
using namespace std;

#define fi first
#define se second
#define pii pair<int,int>
#define pll pair<long long,long long>
#define pb push_back
#define debug(x) cerr<<#x<<"="<<x<<endl
#define pq priority_queue
#define inf 0x3f
#define rep(i,a,b) for (int i=a;i<(b);i++)
#define MP make_pair
#define SZ(x) (int(x.size()))
#define ll long long
#define mod 1000000007
#define ALL(x) x.begin(),x.end()
void inc(int &a,int b) {a=(a+b)%mod;}
void dec(int &a,int b) {a=(a-b+mod)%mod;}
int lowbit(int x) {return x&(-x);}
ll p0w(ll base,ll p) {ll ret=1;while(p>0){if (p%2ll==1ll) ret=ret*base%mod;base=base*base%mod;p/=2ll;}return ret;}

#include "rail.h"

const int maxn = 1e6+10;;
int dis0[maxn],dis1[maxn],dis2[maxn];
int mark[maxn];

void findLocation(int N, int first, int location[], int stype[])
{
	rep(i,0,N) stype[i]=-1;
	location[0] = first;
	stype[0] = 1;
	int pos=1;
	rep(i,1,N) {
		int tmp = getDistance(i,0);
		dis0[i] = tmp;
		if (dis0[i]<dis0[pos]) pos=i;
	}
	location[pos] = first + dis0[pos];
	memset(mark,-1,sizeof(mark));
	mark[location[0]] = 1;
	stype[pos] = 2;
	debug(location[pos]);
	rep(i,0,N) {
		if (i==pos) continue;
		dis1[i] = getDistance(i,pos);
	}
	vector <pii> lft,rit;
	rep(i,1,N) if (stype[i]==-1) {
		if (dis0[i] == dis1[i] + dis1[0]) {
			if (dis1[i]<dis0[pos]) location[i] = location[pos] - dis1[i], stype[i] = 1, mark[location[i]] =1;
			else lft.pb({dis1[i],i});
		}
		else rit.pb({dis0[i],i});
	}
	sort(ALL(lft));
	int cmin = 0;
	for (auto itt:lft) {
		int it = itt.se;
		int hi = getDistance(it,cmin);
//		debug(hi);debug(dis1[it]);
		int tmp = dis1[cmin] + hi - dis1[it];
		tmp/=2;
//		debug(location[cmin]+tmp);
		if (mark[location[cmin] + tmp]==1) {
			stype[it] = 2;
			location[it] = location[cmin] + hi;
		}
		else {
			stype[it] = 1, location[it] = location[pos] - dis1[it];
			cmin = it;
			mark[location[it]] = 1;
		}
	}
	memset(mark,-1,sizeof(mark));
	mark[location[pos]] = 1;
	sort(ALL(rit));
	int dmax = pos;
	for (auto itt:rit) {
		int it = itt.se;
		int hi = getDistance(it,dmax);
		int tmp = dis0[dmax] + hi - dis0[it];
		tmp/=2;
		if (mark[location[dmax] - tmp]==1) {
			stype[it] = 1;
			location[it] = location[dmax] - hi;
		}
		else {
			stype[it] = 2, location[it] = first + dis0[it];
			dmax = it;
			mark[location[it]] = 1;
		}
	}
	return;
}

• Subtask 1: 8 / 8
• Subtask 2: 22 / 22
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44