Monikulmio

#include<bits/stdc++.h>
 
using namespace std;
using ll = long long;
using ld = long double;
 
#define MOD (ll)(998244353LL) //1e9+7
 
int n, m, k;
vector<vector<char>> c;
pair<int, int> dirs[4] = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
 
int main() {
    ios::sync_with_stdio(false); cin.tie(0);
    cin >> n >> m >> k;
    vector<pair<int, int>> p(k);
    for (auto& x : p) cin >> x.first >> x.second;
 
    c.resize(n, vector<char>(m, '#'));
    vector<int> dx(k), dy(k);
    for (int i = 0; i < k; i++) {
        int x = p[i].second-1; int y = p[i].first-1;
        dy[i] = p[(i+1)%k].first - p[i].first;
        dx[i] = p[(i+1)%k].second - p[i].second;
        int z = max(abs(dy[i]), abs(dx[i]));
        char e;
        if (dy[i] != 0) dy[i] = dy[i] > 0 ? 1 : -1;
        if (dx[i] != 0) dx[i] = dx[i] > 0 ? 1 : -1;
        if (dy[i] == 0) {
            e = '=';
        } else if (dx[i] == 0) {
            e = '|';
        } else if (abs(dy[i] + dx[i]) == 2) {
            e = '\\';
        } else { 
            e = '/';
        }
 
        c[y][x] = '*';
        for (int j = 1; j < z; j++) {
            x += dx[i]; y += dy[i];
            c[y][x] = e;
        }
    }
    priority_queue<pair<int, int>> q;
    for (int x = 0; x < m; x++) {
        if (c[0][x] == '#') q.push({0, x});
        if (c[n-1][x] == '#') q.push({n-1, x});
    }
    for (int y = 0; y < n; y++) {
        if (c[y][0] == '#') q.push({y, 0});
        if (c[y][m-1] == '#') q.push({y, m-1});
    }
    while (!q.empty()) {
        pair<int, int> yx = q.top();
        q.pop();
        if (c[yx.first][yx.second] == '.') continue;
        c[yx.first][yx.second] = '.';
        for (const auto& d : dirs) {
            if (yx.first + d.first < 0 || yx.first + d.first >= n || yx.second + d.second < 0 || yx.second + d.second >= m) continue;
            if (c[yx.first + d.first][yx.second + d.second] == '#') q.push({yx.first + d.first, yx.second + d.second});
        }
    }
    for (int y = 0; y < n; y++) {
        for (int x = 0; x < m; x++) {
            cout << c[y][x];
        }
        cout << "\n";
    }
}

Test 1 (public)

Verdict: ACCEPTED

Test 2 (public)

Verdict: ACCEPTED

Test 3 (public)

Verdict: ACCEPTED

Test 4 (public)

Verdict: ACCEPTED

Test 5 (public)

Verdict: ACCEPTED

Test 6 (public)

Verdict: ACCEPTED

Test 7 (public)

Verdict: ACCEPTED

Test 8 (public)

Verdict: ACCEPTED

Test 9 (public)

Verdict: ACCEPTED

Test 10 (public)

Verdict: ACCEPTED