Monikulmio

#include <iostream>
using namespace std;

char art[100][100] = {0};
void connect(int aY, int aX, int bY, int bX) {
  if (aY == bY) {
    int left = min(aX, bX);
    for (int i = 1; i < abs(aX - bX); i++) {
      art[bY][left + i] = '=';
    }
  } else if (aX == bX) {
    int top = min(aY, bY);
    for (int i = 1; i < abs(aY - bY); i++) {
      art[top + i][bX] = '|';
    }
  } else {
    int left;
    int vert1;
    int vert2;
    if (aX < bX) {
      left = aX;
      vert1 = aY;
      vert2 = bY;
    } else {
      left = bX;
      vert1 = bY;
      vert2 = aY;
    }
    if (vert1 > vert2) {
      for (int i = 1; i < abs(aX - bX); i++) {
        art[vert1 - i][left + i] = '/';
      }
    } else {
      for (int i = 1; i < abs(aX - bX); i++) {
        art[vert1 + i][left + i] = '\\';
      }
    }
  }
}

int main() {
  int n, m, k;
  cin >> n >> m >> k;
  int previous[2] = {-1, -1};
  int first[2] = {-1, -1};
  for (int _ = 0; _ < k; _++) {
    int y, x;
    cin >> y >> x;
    --y;
    --x;
    art[y][x] = '*';
    if (first[0] == -1) {
      first[0] = y;
      first[1] = x;
    }
    if (previous[0] != -1) {
      connect(previous[0], previous[1], y, x);
    }
    previous[0] = y;
    previous[1] = x;
  }
  connect(previous[0], previous[1], first[0], first[1]);

  for (int i = 0; i < n; i++) {
    bool inside = false;
    for (int j = 0; j < m; j++) {
      if (art[i][j] == '*') {
        break;
      } else if (art[i][j] == '|' || art[i][j] == '/' || art[i][j] == '\\') {
        inside = !inside;
      } else if (art[i][j] != '=') {
        art[i][j] = inside ? '#' : '.';
      }
    }
  }
  for (int j = 0; j < m; j++) {
    bool inside = false;
    for (int i = 0; i < n; i++) {
      if (art[i][j] == '*') {
        break;
      } else if (art[i][j] == '=' || art[i][j] == '/' || art[i][j] == '\\') {
        inside = !inside;
      } else if (art[i][j] != '|') {
        art[i][j] = inside ? '#' : '.';
      }
    }
  }

  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (art[i][j] == 0) {
        art[i][j] = '.';
      }
    }
  }

  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (art[i][j] == '|' || art[i][j] == '/' || art[i][j] == '=' || art[i][j] == '\\' || art[i][j] == '*' || art[i][j] == '#') continue; // I hate this line so much, but oh well :D
      if (art[i-1][j] == '#' || art[i+1][j] == '#' || art[i][j-1] == '#' || art[i][j+1] == '#') {
        art[i][j] = '#';
      }
    }
  }

  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      cout << art[i][j];
    }
    cout << '\n';
  }
  return 0;
}

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