#include<bits/stdc++.h>
using namespace std;
#define int long long
const int MAXN = 1010;
int n, m, c, a[MAXN][MAXN], ans;
signed main() {
    freopen("land.in", "r", stdin);
    freopen("land.out", "w", stdout);
	cin >> m >> n >> c;
	for(int i = 1; i <= n; i ++) {
		for(int j = 1; j <= m; j ++) {
			cin >> a[i][j];
		}
	}
	for(int i = 1; i <= n; i ++) {
		for(int j = 1; j <= m; j ++) {
			int flg = 1;
			for(int k = i; k <= n; k ++) {
				for(int l = j; l - j + 1 <= 100, l <= m; l ++) {
					int maxn = -1e9, minn = 1e9;
					flg = 1;
					for(int i1 = i; i1 <= k; i1 ++) {
						for(int j1 = j; j1 <= l; j1 ++) {
							maxn = max(maxn, a[i1][j1]);
							minn = min(minn, a[i1][j1]);
							if(maxn - minn > c) {
								flg = 0;
								break;
							}
						}
						if(!flg) {
							break;
						}
					}
					if(flg) {
						int x = (k - i + 1) * (l - j + 1);
						if(x > ans) {
//							cout << i << ' ' << j << ' ' << k << ' ' << l << endl;
						}
						ans = max(ans, x);
					}
					else {
						break;
					}
				}
			}
		}
	}
	cout << ans;
	return 0;
}