Mikołaj Dziok - wyspy

#include <bits/stdc++.h>

using namespace std;

bool sea[1010][1010];

int main()
{
    int n,m;
    cin >> n >> m;
    string boi;
    int res = 0;
    for (int i = 0;i<n;i++)
    {
        cin >> boi;
        for (int j = 0;j<m;j++)
        {
            if (boi[j] == '1')
            {
                sea[i+1][j+1] = 1;
                int temp = sea[i][j+1] + sea[i+1][j];
                if (temp == 0)
                    res++;
                if (temp == 2)
                    if (sea[i][j] == 0)
                        res--;
            }
        }
    }
    cout << res;
    return 0;
}