Submission #864514

#	Time	Username	Problem	Language	Result	Execution time	Memory
864514		suiyeet	Roller Coaster Railroad (IOI16_railroad)	C++14	0 / 100	567 ms	45700 KiB

railroad

#include "railroad.h"
#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
void debug_out() {cerr<<endl;}
template <typename Head, typename... Tail>
void debug_out(Head _H, Tail... _T) {cerr<<" "<<to_string(_H);debug_out(_T...);}
#define debug(...) cerr<<"["<<#__VA_ARGS__<<"]:",debug_out(__VA_ARGS__)
#else
#define debug(...)
#endif
const int MAXN = 600005;
const int inf=1000000500ll;
const long long oo =1000000000000000500ll;
const int MOD = (int)1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef pair<int,int> pi; 
struct fenw {
    int fw[MAXN];
    void update(int x, int nval){
        for(;x<MAXN;x+=x&-x)fw[x]+=nval;
    }
    void update(int x, int y, int nval){
        update(x,nval);
        update(y+1,-nval);
    }
    int point(int x){
        int res=0;
        for(;x;x-=x&-x)res+=fw[x];
        return res;
    }
}fw;
namespace ufds{
    int p[MAXN];
    int sz[MAXN];
    int find(int x){
        if(p[x]==x)return x;
        else return p[x]=find(p[x]);
    }
    void merge(int x, int y){
        x=find(x);y=find(y);
        if(x==y)return;
        if(sz[x]<sz[y])swap(sz[x],sz[y]);
        sz[x]+=sz[y];
        p[y]=x;
    }
};
long long plan_roller_coaster(std::vector<int> s, std::vector<int> t) {
    iota(ufds::p,ufds::p+MAXN,0);
    fill(ufds::sz,ufds::sz+MAXN,1);
    s.push_back(1e9);
    t.push_back(1);
    vector<int>points;
    map<int,int> mp;
    int n=s.size();
    for(int i=0;i<n;i++){
        if(s[i]==t[i]){
            points.push_back(s[i]);
        } else if(s[i]<t[i]){
            points.push_back(s[i]);
            points.push_back(t[i]);
            points.push_back(t[i]-1);
        } else if(s[i]>t[i]){
            points.push_back(s[i]-1);
            points.push_back(s[i]);
            points.push_back(t[i]);
        }
    }
    sort(points.begin(),points.end());
    points.resize(unique(points.begin(),points.end())-points.begin());
    for(int i=0;i<points.size();i++){
        mp[points[i]]=i+1;
    }
    for(int i=0;i<n;i++){
        if(s[i] == t[i])continue;
        ufds::merge(mp[s[i]],mp[t[i]]);
        if(s[i]<t[i]){
            fw.update(mp[s[i]],mp[t[i]-1],1);
        } else {
            fw.update(mp[t[i]],mp[s[i]-1],-1);
        }
        
    }
    int m=points.size();
    for(int i=1;i<=m;i++){
        int r=fw.point(i);
        if(r>0)return 1;
        if(r<0){
            ufds::merge(i,i+1);
        }
    }
    for(int i=1;i<=m;i++){
        if(ufds::find(i) != ufds::find(1)){
            return 1;
        }
    }

    return 0;
}

Compilation message (stderr)

railroad.cpp: In function 'long long int plan_roller_coaster(std::vector<int>, std::vector<int>)':
railroad.cpp:71:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |     for(int i=0;i<points.size();i++){
      |                 ~^~~~~~~~~~~~~~

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