Submission #116008

#	Time	Username	Problem	Language	Result	Execution time	Memory
116008		Meloric	Triangles (CEOI18_tri)	C++14	0 / 100	2 ms	384 KiB

tri

#include "trilib.h"
#include <bits/stdc++.h>
#define pb push_back
#define X first
#define Y second
#define pii pair<int, int>

using namespace std;
/*
int get_n(){
    int c; cin >> c;
    return c;
}
void give_answer(int a){
    cout << a;
}
bool is_clockwise(int a, int b, int c){
    cout << a << ' '<<b <<' '<<c<<endl;
    bool d; cin >> d;
    return d;
}*/
bool ask(int a, int b, int c){
    a++; b++; c++;
    return is_clockwise(a, b, c);
}
bool cmp(int a, int b){
    return !ask(0, a, b);
}
int main(){
    ios_base::sync_with_stdio(false);
    int n; n = get_n();
    if(n==3)give_answer(3);
    vector<int> up, dw, srt, hull;
    for(int i = 2; i < n; i++){
        if(ask(0, 1, i))up.pb(i);
        else dw.pb(i);
    }
    sort(up.begin(), up.end(), cmp);
    sort(dw.begin(), dw.end(), cmp);
    dw.pb(0), up.pb(1);
    for(int i : up)srt.pb(i);
    for(int i : dw)srt.pb(i);
    for(int i = 0; i < srt.size(); i++){
        int sz = hull.size();
        while(sz>1 && ask(hull[sz-2], hull[sz-1], srt[i])){
            hull.pop_back();
            sz--;
        }
        hull.pb(srt[i]);
    }
    deque<int> dq;
    for(auto i : hull)dq.pb(i);
    while(1){
        int flag = 1;
        int cur = dq.back(); dq.pop_back();
        if(ask(dq.back(), cur, dq.front())){
            flag = 0;
        }else dq.pb(cur);
        cur = dq.front(); dq.pop_front();
        if(ask(dq.back(), cur, dq.front())){
            flag = 0;
        }else dq.push_front(cur);
        if(flag)break;
    }
    give_answer(dq.size());
    return 0;
}

Compilation message (stderr)

tri.cpp: In function 'int main()':
tri.cpp:43:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < srt.size(); i++){
                    ~~^~~~~~~~~~~~

• Subtask 1: 0 / 15
• Subtask 2: 0 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 20
• Subtask 5: 0 / 25