Submission #864443

#	Time	Username	Problem	Language	Result	Execution time	Memory
864443		suiyeet	Roller Coaster Railroad (IOI16_railroad)	C++14	0 / 100	559 ms	26180 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 = -1;
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; 
multiset<pi> in, out;
bool bad;
pi findin(pi cur){
    in.erase(in.find({cur.first,cur.second}));
    auto it=in.lower_bound({cur.second,0});
    if(it==in.end()){
        bad=1;
        return {-1,-1};
    } else{
        pi res=*it;
        in.insert({cur.first,cur.second});
        return res;
    }
}
pi findout(pi cur){
    out.erase(out.find({cur.second,cur.first}));
    auto it=out.lower_bound({cur.first,inf});
    assert(it!=out.begin());
    auto pre=prev(it);
    pi res=*pre;
    out.insert({cur.second,cur.first});
    return res;
}
long long plan_roller_coaster(std::vector<int> s, std::vector<int> t) {
    
    int n=s.size();
    for(int i=0;i<n;i++){
        in.insert({s[i],t[i]});
        out.insert({t[i],s[i]});
    }
    while((int)out.size() > 1){
        pi t=*out.begin();
        pi pin=findin({t.second,t.first});
        if(bad)return 1;
        pi pout=findout({pin.first,pin.second});

        swap(pout.first,pout.second);
        //debug(pin.first,pin.second,pout.first,pout.second);

        in.erase(in.find(pin));

        in.erase(in.find(pout));

        out.erase(out.find({pout.second,pout.first}));

        out.erase(out.find({pin.second,pin.first}));



        pi newtrack={pout.first,pin.second};

        in.insert({newtrack.first,newtrack.second});
        out.insert({newtrack.second,newtrack.first});
    }
    return 0;
}

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