#include <bits/stdc++.h>

using namespace std;
using ll = long long;
#define rep(i, s, t) for (ll i = s; i < (ll)(t); i++)
#define all(x) begin(x), end(x)
template <class T> bool chmin(T& x, T y) {
	return x > y ? (x = y, true) : false;
}
template <class T> bool chmax(T& x, T y) {
	return x < y ? (x = y, true) : false;
}

void solve() {
	int h, w, sx, sy, n;
	cin >> h >> w >> sx >> sy >> n;
	sx--, sy--;
	ll bf1 = 0, bf2 = -1e18;
	while (n--) {
		int x, y, c;
		cin >> x >> y >> c;
		x--, y--;
		ll sc = 0;
		chmax(sc, bf2 + c);
		if (x == sx || y == sy || x + y == sx + sy || x - y == sx - sy) {
			chmax(sc, bf1 + c);
		}
		sx = x, sy = y;
		bf2 = bf1;
		bf1 = sc;
	}
	cout << max(bf1, bf2) << '\n';
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout << fixed << setprecision(15);
	int t = 1;
	// cin >> t;
	while (t--) solve();
}