#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
const int INF = 0x3f3f3f3f;
const ll mod = 998244353;
const int N = 5e2 + 10;
int a[N][N], dp[N][N];
int dx[] = {1, -1, 0, 0};
int dy[] = {0, 0, 1, -1};
int n, m, d, ans;

void dfs(int x, int y, int cnt) {
	if (dp[x][y] != 0) {
		return;
	}
	dp[x][y] = cnt;
	for (int i = 0; i < 4; i++) {
		int nx = x + dx[i];
		int ny = y + dy[i];
		if (nx >= 1 && nx <= n && ny >= 1 && ny <= m && abs(a[nx][ny] - a[x][y]) <= d) {
			dfs(nx, ny, cnt);
		}
	}
}

int main() {
	scanf("%d%d%d", &n, &m, &d);
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			scanf("%d", &a[i][j]);
		}
	}
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			if (dp[i][j] == 0) {
				ans++;
				dfs(i, j, ans);
			}
		}
	}
	printf("%d", ans);
	return 0;
}