#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
// using namespace atcoder;
// using mint = modint1000000007;
// const int mod = 1000000007;
// using mint = modint998244353;
// const int mod = 998244353;
// const int INF = 1e9;
const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i, l, r) for (int i = (l); i < (r); ++i)
#define rrep(i, n) for (int i = (n)-1; i >= 0; --i)
#define rrep2(i, l, r) for (int i = (r)-1; i >= (l); --i)
#define all(x) (x).begin(), (x).end()
#define allR(x) (x).rbegin(), (x).rend()
#define P pair<int, int>
template<typename A, typename B> inline bool chmax(A& a, const B& b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A& a, const B& b) { if (a > b) { a = b; return true; } return false; }

int main() {
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);
	int h, w; cin >> h >> w;
	int sx, sy; cin >> sx >> sy;
	int n; cin >> n;
	auto move = [](P p, P q) -> bool {
		int dx = p.first - q.first;
		int dy = p.second - q.second;
		return dx == 0 || dy == 0 || abs(dx) == abs(dy);
	};
	vector<long long>c(n + 1);
	vector<P>p(n + 1);
	p[0] = { sx,sy };
	rep(i, n)cin >> p[i + 1].first >> p[i + 1].second >> c[i + 1];


	vector<long long> dp(2, -LINF);
	dp[0] = 0;
	rep2(i, 1, n + 1) {
		vector<long long> ndp(2, -LINF);
		chmax(ndp[1], dp[0] + c[i]);
		chmax(ndp[0], dp[1] + 0);
		chmax(ndp[0], dp[0] + 0);
		if (move(p[i - 1], p[i]))chmax(ndp[1], dp[1] + c[i]);
		dp.swap(ndp);
	}
	auto ans = *max_element(all(dp));
	cout << ans << endl;
	return 0;
}