Untitled

#include <iostream>
#include <fstream>
using namespace std;

int N, K, board[100][10], region[100][10], regsizes[1001];

void gravity(void)
{
    for (int j=0; j<10; j++) {
        int top = N-1, bottom = N-1;
        while (top >= 0) {
            while (top >= 0 && board[top][j] == 0) top--;
            if (top >= 0)
                board[bottom--][j] = board[top--][j];
        }
        while (bottom >= 0) board[bottom--][j] = 0;
    }
}

void visit(int i, int j, int r, int c)
{
    if (i<0 || i>=N || j<0 || j>9 || board[i][j]!=c || region[i][j]!=0) return;
    region[i][j] = r;
    regsizes[r]++;
    visit(i-1,j,r,c);
    visit(i+1,j,r,c);
    visit(i,j-1,r,c);
    visit(i,j+1,r,c);
}

bool iterate(void)
{
    int r = 1;
    for (int i=0; i<N; i++)
        for (int j=0; j<10; j++)
            region[i][j] = 0;
    for (int i=0; i<N; i++)
        for (int j=0; j<10; j++)
            if (board[i][j] && !region[i][j]) visit(i,j,r++,board[i][j]);
    bool progress = false;
    for (int i=0; i<N; i++)
        for (int j=0; j<10; j++)
            if (board[i][j] && regsizes[region[i][j]]>=K) {
                board[i][j] = 0;
                progress = true;
            }
    gravity();
    while (r) regsizes[r--] = 0;
    return progress;
}

int main(void)
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    cin >> N >> K;
    string s;

    for (int i=0; i<N; i++) {
        cin >> s;
        for (int j=0; j<10; j++) board[i][j] = s[j]-'0';
    }

    while (iterate());

    for (int i=0; i<N; i++) {
        for (int j=0; j<10; j++) cout << board[i][j];
        cout << "\n";
    }
    return 0;
}