Submission #407177

#	Time	Username	Problem	Language	Result	Execution time	Memory
407177		Victor	Triangles (CEOI18_tri)	C++17	55 / 100	5 ms	972 KiB

tri

#include <bits/stdc++.h>

#include "trilib.h"

using namespace std;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define per(i, a, b) for (int i = b - 1; i >= (a); --i)
#define trav(a, x) for (auto &a : x)

#define all(x) x.begin(), x.end()
#define sz(x) x.size()
#define pb push_back

#define umap unordered_map
#define uset unordered_set

typedef pair<int, int> ii;
typedef pair<int, ii> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<vi> vvi;
typedef long long ll;

const int INF = 1000000007;


int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);

    bitset<501> taken;
    int city;
    int n = get_n();

    assert(n<=500);

    rep(i, 1, n + 1) {
        int nxt = i == 1 ? 2 : 1;
        rep(j, 1, n + 1) {
            if (i == j || j == nxt) continue;
            if (is_clockwise(i, nxt, j)) nxt = j;
        }

        bool onborder = true;
        rep(j, 1, n + 1) {
            if (i == j || j == nxt) continue;
            if (is_clockwise(i, nxt, j)) onborder = false;
        }

        if (onborder) {
            city = nxt;
            taken[i] = 1;
        }
    }

    while (!taken[city]) {
        taken[city] = 1;
        int nxt = city == 1 ? 2 : 1;

        rep(j, 1, n + 1) {
            if (city == j || j == nxt) continue;
            if (is_clockwise(city, nxt, j)) nxt = j;
        }

        city=nxt;
    }

    cout << taken.count() << endl;
    return 0;
}

Compilation message (stderr)

tri.cpp: In function 'int main()':
tri.cpp:33:9: warning: 'city' may be used uninitialized in this function [-Wmaybe-uninitialized]
   33 |     int city;
      |         ^~~~

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