#include <iostream>
#include <vector>
#include <map>
#include <queue>
#include <utility>

using namespace std;

int main()
{
    int n, m;
    cin >> n >> m;
    vector<vector<int>> a(n + 2, vector<int>(m + 2, 0));
    for (int i = 1; i <= n; ++i) {
        for (int l = 1; l <= m; ++l) {
            cin >> a[i][l];
        }
    }
    map<pair<int, int>, int> used;
    long long k = 0;
    for (int i = 1; i <= n; ++i) {
        for (int l = 1; l <= m; ++l) {
            if (used[{i, l}] == 0) {
                k++;
                queue<pair<int, int>> q;
                q.push({ i, l });
                while (!q.empty()) {
                    auto p = q.front();
                    q.pop();
                    used[p] = 1;
                    if (a[p.first][p.second] == a[p.first - 1][p.second] && used[{ p.first - 1, p.second }] == 0) {
                        q.push({ p.first - 1, p.second });
                    }
                    if (a[p.first][p.second] == a[p.first][p.second + 1] && used[{ p.first, p.second + 1 }] == 0) {
                        q.push({ p.first, p.second + 1 });
                    }
                    if (a[p.first][p.second] == a[p.first + 1][p.second] && used[{ p.first + 1, p.second }] == 0) {
                        q.push({ p.first + 1, p.second });
                    }
                    if (a[p.first][p.second] == a[p.first][p.second - 1] && used[{ p.first, p.second - 1 }] == 0) {
                        q.push({ p.first, p.second - 1 });
                    }
                }
            }
        }
    }
    cout << k;
}