#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return true; } return false; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return true; } return false; }
#define vi vector<int>
#define vl vector<ll>
#define vii vector<pair<int,int>>
#define vll vector<pair<ll,ll>>
#define vvi vector<vector<int>>
#define vvl vector<vector<ll>>
#define vvii vector<vector<pair<int,int>>>
#define vvll vector<vector<pair<ll,ll>>>
#define vst vector<string>
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pb push_back
#define all(x) (x).begin(),(x).end()
#define mkunique(x) sort(all(x));(x).erase(unique(all(x)),(x).end())
#define fi first
#define se second
#define mp make_pair
#define si(x) int(x.size())
const int mod=998244353,MAX=500005,INF=15<<26;

bool ONE(ll a,ll b,ll c,ll d){
    return (a==c||b==d||a+b==c+d||a-b==c-d);
}

ll dp[MAX];

int main(){
    
    std::ifstream in("text.txt");
    std::cin.rdbuf(in.rdbuf());
    cin.tie(0);
    ios::sync_with_stdio(false);
    
    ll H,W;cin>>H>>W;
    ll sh,sw;cin>>sh>>sw;sh--;sw--;
    ll N;cin>>N;
    vector<array<ll,3>> S(N+1);
    assert(0<=sh&&sh<H);
    assert(0<=sw&&sw<W);
    for(int i=1;i<=N;i++){
        ll a,b,c;cin>>a>>b>>c;a--;b--;
        assert(0<=a&&a<H);
        assert(0<=b&&b<W);
        assert(1<=c);
        S[i]={a,b,c};
    }
    S[0]={sh,sw,0};
    
    for(int i=1;i<=N;i++){
        dp[i]=-(15LL<<58);
        if(ONE(S[i-1][0],S[i-1][1],S[i][0],S[i][1])) chmax(dp[i],dp[i-1]+S[i][2]);
        if(i>=2) chmax(dp[i],dp[i-2]+S[i][2]);
        if(i>=3) chmax(dp[i],dp[i-3]+S[i][3]);
    }
    ll res=-1;
    for(int i=0;i<=N;i++){
        chmax(res,dp[i]);
    }
    cout<<res<<endl;
}