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

void solve(){
	long long inf=1e18;
	auto f=[&](int i1,int j1,int i2,int j2){
		int di=abs(i1-i2),dj=abs(j1-j2);
		if (di==0&&dj==0) return true;
		if (di==0||dj==0||di==dj) return true;
		return false;
	};
	int h,w,sx,sy,n;
	cin>>h>>w>>sx>>sy>>n;
	sx--;sy--;
	vector<int> x(n+1),y(n+1),c(n+1);
	x[0]=sx;y[0]=sy;c[0]=0;
	for (int i=0;i<n;i++) cin>>x[i+1]>>y[i+1]>>c[i+1],x[i+1]--,y[i+1]--;
	vector<long long> dp(n+1,-inf),dpmax(n+1,-inf);
	dp[0]=dpmax[0]=0;
	for (int i=0;i<n;i++){
		if (f(x[i],y[i],x[i+1],y[i+1])) dp[i+1]=max(dp[i+1],dp[i]+c[i+1]);
		if (i) dp[i+1]=max(dp[i+1],dpmax[i-1]+c[i+1]);
		dpmax[i+1]=max(dpmax[i],dp[i+1]);
	}
	cout<<dpmax[n]<<endl;
}

int main(){
	int t=1;
	//cin>>t;
	while (t--) solve();
}