Решение задачи Дырявая ткань с Меньшиков

#include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#include <algorithm>
 
using namespace std;
 
const int MAX_SIZE = 110;
const int FREE = 0;
const int USED = 7;
int n,m;
vector<vector<int> > mas;
void input()
{
    cin>>m>>n;
    mas = vector<vector<int> >(n+4,vector<int>(m+4,0));
 
    char str[MAX_SIZE];
    for (int i=2;i<n+2;i++)
    {
        scanf("%s",str);
        for (int j=2; j<m+2; j++)
            mas[i][j] = (str[j-2] == '*' ? USED : FREE);
    }
}
struct point
{
    int x,y;
    point(){}
    point(int X, int Y)
    {
        x = X;
        y = Y;
    }
};
int moveX[4] = {0,-1,0,1};
int moveY[4] = {-1,0,1,0};
vector<int> holes;
vector<int> squares;
bool correct(int x, int y)
{
    if (x<0 || y<0)
        return false;
    if (x==n+4 || y==m+4)
        return false;
    return true;
}
int bfs1(int X, int Y, vector<vector<int> > &one, int &minX, int &maxX, int &minY, int &maxY)
{
    int S = 1;
    mas[X][Y] = FREE;
    one[X][Y] = USED;
    queue<point> q;
    q.push(point(X,Y));
    while (!q.empty())
    {
        point cur = q.front(); q.pop();
        for (int i=0;i<4;i++)
        {
            int x = cur.x + moveX[i];
            int y = cur.y + moveY[i];
           
            if (correct(x,y) && mas[x][y] == USED)
            {
                minX = min(minX, x);
                maxX = max(maxX, x);
                minY = min(minY, y);
                maxY = max(maxY, y);
 
                S++;
                mas[x][y] = FREE;
                one[x][y] = USED;
                q.push(point(x,y));
            }
        }
    }
    return S;
}
void prepare(vector<vector<int> > &one, int minX, int maxX, int minY, int maxY)
{
    for (int i = minX - 1; i <= maxX + 1; i++)
    {
        one[i][minY-1] = FREE; one[i][minY-2] = USED;
        one[i][maxY+1] = FREE; one[i][maxY+2] = USED;
    }
    for (int i = minY - 1; i <= maxY + 1; i++)
    {
        one[minX-1][i] = FREE; one[minX-2][i] = USED;
        one[maxX+1][i] = FREE; one[maxX+2][i] = USED;
    }
}
void bfs2 (vector<vector<int> > &one, int x, int y)
{
    one[x][y] = USED;
    queue<point> q;
    q.push(point(x,y));
    while (!q.empty())
    {
        point cur = q.front(); q.pop();
        for (int i=0;i<4;i++)
        {
            int x = cur.x + moveX[i];
            int y = cur.y + moveY[i];
            if (one[x][y] == FREE) // проверка correct(x,y) не нужна
            {
                one[x][y] = USED;
                q.push(point(x,y));
            }
        }
    }
}
int findHols(vector<vector<int> > &one, int minX, int maxX, int minY, int maxY)
{
    int holesAmount = -1;
    for (int i = minX - 1; i < maxX + 1; i++)
    {
        for (int j = minY - 1; j< maxY + 1; j++)
        {
            if (one[i][j] == FREE)
            {
                bfs2(one, i, j);
                holesAmount++;
            }
        }
    }
    return holesAmount;
}
void solve()
{
    vector<vector<int> > one = vector<vector<int> >(n+4,vector<int>(m+4));
    for (int i=2;i<n+2;i++)
    {
        for (int j=2;j<m+2;j++)
        {
            if (mas[i][j] == USED)
            {       
                for (int p=0;p<n+4;p++)
                    one[p].assign(one[p].size(),FREE);
                int minX = i, maxX = i;
                int minY = j, maxY = j;
                int curS = bfs1(i,j,one,minX,maxX,minY,maxY);
                prepare(one, minX, maxX, minY,maxY);
                int holesAmount = findHols(one,minX,maxX,minY,maxY);
                if (holesAmount != 0)
                {
                    holes.push_back(holesAmount);
                    squares.push_back(curS);
                }
            }
        }
    }
    if (holes.empty())
    {
        cout<<0;
        return;
    }
    int pos = max_element(holes.begin(),holes.end()) - holes.begin();
    int maxHoles = holes[pos];
    int minSquare = squares[pos];
    for (int i=0;i<squares.size();i++)
    {
        if (holes[i] == maxHoles)
            minSquare = min(minSquare,squares[i]);
    }
    cout<<minSquare;
}
int main()
{
#ifdef _DEBUG
    freopen("input.txt","r",stdin);
    freopen("output.txt","w",stdout);
#endif
 
    input();
    solve();
    return 0;
}