Submission #123849

#	Time	Username	Problem	Language	Result	Execution time	Memory
123849		baluteshih	Crocodile's Underground City (IOI11_crocodile)	C++14	100 / 100	885 ms	87068 KiB

crocodile

#include "crocodile.h"
#include<bits/stdc++.h>
#define MP make_pair
#define F first
#define S second
#define pb push_back
#define MEM(i,j) memset(i,j,sizeof i)
#define ET cout << "\n"
#define ALL(v) v.begin(),v.end()
#define DB(a,s,e) {for(int i=s;i<e;++i) cout << a[i] << " ";ET;}
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

const ll INF=1e18;
vector<pll> G[100005];
pll dp[100005];
bitset<100005> vis;

struct node
{
	ll i;
	node operator+(const node &x)const{
		if(vis[x.i]||vis[i]) return vis[i]?node{x.i}:node{i};
		return dp[x.i].S<dp[i].S?node{x.i}:node{i};
	}
}seg[400005];

void build(int l,int r,int rt)
{
	if(l==r) 
		return seg[rt].i=l,void();
	int m=l+r>>1;
	build(l,m,rt<<1),build(m+1,r,rt<<1|1);
	seg[rt]=seg[rt<<1]+seg[rt<<1|1];
}

void modify(int x,int l,int r,int rt)
{
	if(l==r)
		return;
	int m=l+r>>1;
	if(x<=m) modify(x,l,m,rt<<1);
	else modify(x,m+1,r,rt<<1|1);
	seg[rt]=seg[rt<<1]+seg[rt<<1|1];
}

int travel_plan(int N, int M, int R[][2], int L[], int K, int P[])
{
	for(int i=0;i<N;++i)
		dp[i]=MP(INF,INF);
	for(int i=0;i<M;++i)
		G[R[i][0]].pb(MP(L[i],R[i][1])),G[R[i][1]].pb(MP(L[i],R[i][0]));
	for(int i=0;i<K;++i)
		dp[P[i]]=MP(0,0);
	build(0,N-1,1);
	for(int i=0;i<N;++i)
	{
		int mi=seg[1].i;
		vis[mi]=1;
		modify(mi,0,N-1,1);
		for(auto j:G[mi])
			if(!vis[j.S])
			{
				ll x=dp[mi].S+j.F;
				if(x<dp[j.S].F)
					dp[j.S].S=dp[j.S].F,dp[j.S].F=x,modify(j.S,0,N-1,1);
				else if(x<dp[j.S].S)
					dp[j.S].S=x,modify(j.S,0,N-1,1);
			}
	}
	return dp[0].S;
}

Compilation message (stderr)

crocodile.cpp: In function 'void build(int, int, int)':
crocodile.cpp:34:9: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int m=l+r>>1;
        ~^~
crocodile.cpp: In function 'void modify(int, int, int, int)':
crocodile.cpp:43:9: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int m=l+r>>1;
        ~^~

• Subtask 1: 46 / 46
• Subtask 2: 43 / 43
• Subtask 3: 11 / 11