Submission #287424

#	Time	Username	Problem	Language	Result	Execution time	Memory
287424		egekabas	Rail (IOI14_rail)	C++14	0 / 100	90 ms	888 KiB

rail

#include "rail.h"
#include <bits/stdc++.h>
#define all(x) (x).begin(), (x).end()
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<int, int> pii;
typedef pair<ld, ld> pld;
int n;
void findLocation(int N, int first, int location[], int stype[]){
    n = N;
    location[0] = first;
    stype[0] = 1;
    pii lef = {first, 0};
    vector<pii> vec;
    for(int i = 1; i < n; ++i){
        vec.pb({getDistance(0, i), i});
    }
    sort(all(vec));
    location[vec[0].ss] = first + vec[0].ff;
    stype[vec[0].ss] = 2;
    set<int> up = {location[vec[0].ss]};
    set<int, greater<int>> down = {first};
    pii rig = {location[vec[0].ss], vec[0].ss};
    for(int i = 1; i < vec.size(); ++i){
        int dis0 = vec[i].ff;
        int idx = vec[i].ss;
        int disl = getDistance(lef.ss, idx);
        int disr = getDistance(rig.ss, idx);

        if(rig.ff-disr >= lef.ff){
            auto it = up.upper_bound(rig.ff-disr);
            if(it == up.end() || disl != 2*(*it)-lef.ff-(rig.ff-disr)){
                stype[idx] = 2;
                location[idx] = lef.ff+disl;
                rig = max(rig, {location[idx], idx});
                up.insert(location[idx]);
            
            }
            else{
                stype[idx] = 1;
                location[idx] = rig.ff-disr;
                lef = min(lef, {location[idx], idx});
                down.insert(location[idx]);
            }
        }
        else if(lef.ff + disl <= rig.ff){
            auto it = down.upper_bound(lef.ff+disl);
            if(it != down.end() && disr == rig.ff+lef.ff+disl-2*(*it)){
                stype[idx] = 2;
                location[idx] = lef.ff+disl;
                rig = max(rig, {location[idx], idx});
                up.insert(location[idx]);
            
            }
            else{
                stype[idx] = 1;
                location[idx] = rig.ff-disr;
                lef = min(lef, {location[idx], idx});
                down.insert(location[idx]);
            }
        }
        else{
            assert(0);
        }
    }
}

Compilation message (stderr)

rail.cpp: In function 'void findLocation(int, int, int*, int*)':
rail.cpp:32:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |     for(int i = 1; i < vec.size(); ++i){
      |                    ~~^~~~~~~~~~~~
rail.cpp:33:13: warning: unused variable 'dis0' [-Wunused-variable]
   33 |         int dis0 = vec[i].ff;
      |             ^~~~

• Subtask 1: 0 / 8
• Subtask 2: 0 / 22
• Subtask 3: 0 / 26
• Subtask 4: 0 / 44