Submission #637007

#	Time	Username	Problem	Language	Result	Execution time	Memory
637007		ggoh	Roller Coaster Railroad (IOI16_railroad)	C++14	30 / 100	93 ms	12216 KiB

railroad

#include<bits/stdc++.h>
#include "railroad.h"
using namespace std;
#define sz(v) ((int)(v).size())
typedef long long lint;
typedef pair<int,int> pii;

lint D[1<<16][16];
int v[200002];
int line[200002],to[200002],rev[200002],sT[200002],num[200002],col;
void dfs(int p)
{
    v[p]=col;
    if(!v[sT[to[p]]])dfs(sT[to[p]]);
}
lint plan_roller_coaster(vector<int> s, vector<int> t) {

    int n = (int) s.size();

    int ch=0;
    vector<pii>S;
    vector<pii>T;
    for(int i=0;i<n;i++)S.push_back({s[i],i});
    for(int i=0;i<n;i++)T.push_back({t[i],i});
    S.push_back({1e9+1,n});T.push_back({0,n});

    sort(S.begin(),S.end());
    sort(T.begin(),T.end());
    for(int i=0;i<=n;i++)num[T[i].second]=i;
    int j=0;
    for(int i=0;i<=n;i++)
    {
        while(j<=n && T[i].first>S[j].first)j++;
        line[i]=j;
        if(j>i)
        {
            return 1;
        }
        to[i]=i;rev[i]=i;
        sT[i]=num[S[i].second];
    }
    col=0;
    for(int i=0;i<=n;i++)
    {
        if(!v[i])
        {
            col++;
            dfs(i);
        }
    }
    int real[200002];
    for(int i=1;i<=col;i++)real[i]=i;
    for(int i=0;i<=n;i++)
    {
        if(real[v[line[i]]]!=real[v[i]])
        {
            real[v[i]]=real[v[line[i]]]=min(real[v[i]],real[v[line[i]]]);
        }
    }
    for(int i=1;i<=col;i++)if(real[i]!=1)return 1;
    return 0;
}

Compilation message (stderr)

railroad.cpp: In function 'lint plan_roller_coaster(std::vector<int>, std::vector<int>)':
railroad.cpp:20:9: warning: unused variable 'ch' [-Wunused-variable]
   20 |     int ch=0;
      |         ^~

• Subtask 1: 0 / 11
• Subtask 2: 0 / 23
• Subtask 3: 30 / 30
• Subtask 4: 0 / 36