Submission #1053573

#	Time	Username	Problem	Language	Result	Execution time	Memory
1053573		anton	Triangles (CEOI18_tri)	C++17	55 / 100	61 ms	604 KiB

tri

#include<bits/stdc++.h>
#include"trilib.h"

using namespace std;
int N;

int get_cand(int u){
    int cur= 0;
    if(u == 0){
        cur++;
    }
    for(int i = 0; i<N; i++){
        if(i!=u  && i!=cur && u!=cur){
            if(is_clockwise(u+1, cur+1, i+1)){
                cur= i;
            }
        }
    }
    return cur;
}

bool is_bound(int a, int b){
    for(int i = 0; i<N; i++){
        if(i!= a && i!=b && a!=b){
            if(is_clockwise(a+1, b+1, i+1)){
                return false;
            }
        }
    }
    return true;
}

signed main(){
    N = get_n();

    int res= 0;
    
    int cur_point =0;
    int hull_begin = -1;
    for(int i = 0; i<N &&hull_begin ==-1; i++){
        int j = get_cand(i);
        if(is_bound(i, j)){
            res++;
            hull_begin = i;
            cur_point = j;
        }
    }

    while(cur_point != hull_begin){
        cur_point = get_cand(cur_point);
        res++;
    }

    cout<<res<<endl;
}

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