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

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int h, w, y, x, n;
    cin >> h >> w >> y >> x >> n;
    vector<ll> dp(n);
    for(int i = 0; i < n; i++){
        int Y, X, V;
        cin >> Y >> X >> V;
        if(Y == y || X == x || abs(Y - y) == abs(X - x)){
            dp[i] = max(i >= 2 ? dp[i - 2] : 0, i >= 1 ? dp[i - 1] : 0) + V;
        }else{
            dp[i] = max(i >= 1 ? dp[i - 1] : -(1 << 30), i >= 2 ? dp[i - 2] + V : V);
        }
        y = Y, x = X;
    }
    cout << max(dp[n - 1], dp[n - 2]) << '\n';
}