#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
template<typename T> inline bool chmax(T &a, T b) { return ((a < b) ? (a = b, true) : (false)); }
template<typename T> inline bool chmin(T &a, T b) { return ((a > b) ? (a = b, true) : (false)); }
#define rep(i, n) for (long long i = 0; i < (long long)(n); i++)
#define rep2(i, m ,n) for (int i = (m); i < (long long)(n); i++)
#define REP(i, n) for (long long i = 1; i < (long long)(n); i++)
typedef long long ll;
#define updiv(N,X) (N + X - 1) / X
#define l(n) n.begin(),n.end()
#define YesNo(Q) Q==1?cout<<"Yes":cout<<"No"
using P = pair<int, int>;
using mint = modint;
const int MOD = 998244353LL;
const ll INF = 999999999999LL;
vector<long long> fact, fact_inv, inv;
/*  init_nCk :二項係数のための前処理
    計算量:O(n)
*/
template <typename T>
void input(vector<T> &v){
 rep(i,v.size()){cin>>v[i];}
  return;
}
void init_nCk(int SIZE) {
    fact.resize(SIZE + 5);
    fact_inv.resize(SIZE + 5);
    inv.resize(SIZE + 5);
    fact[0] = fact[1] = 1;
    fact_inv[0] = fact_inv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < SIZE + 5; i++) {
        fact[i] = fact[i - 1] * i % MOD;
        inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
        fact_inv[i] = fact_inv[i - 1] * inv[i] % MOD;
    }
}
/*  nCk :MODでの二項係数を求める(前処理 int_nCk が必要)
    計算量:O(1)
*/
long long nCk(int n, int k) {
    assert(!(n < k));
    assert(!(n < 0 || k < 0));
    return fact[n] * (fact_inv[k] * fact_inv[n - k] % MOD) % MOD;
}

long long modpow(long long a, long long n, long long mod) {
    long long res = 1;
    while (n > 0) {
        if (n & 1) res = res * a % mod;
        a = a * a % mod;
        n >>= 1;
    }
    return res;
}

ll POW(ll a,ll n){
  long long res = 1;
    while (n > 0) {
        if (n & 1) res = res * a;
        a = a * a;
        n >>= 1;
    }
    return res;
}

int main() {
 int h,w;cin>>h>>w;
 ll x,y;cin>>x>>y;x--;y--;
 int n;cin>>n;
 map<pair<ll,ll>,ll> mp;
 unordered_map<ll,ll> mp1,mp2,mp3,mp4;
 mp[pair(x,y)] = 0;
 mp1[x]=0;
 mp2[y]=0;
 mp3[x-y]=0;
 mp4[x+y]=0;
 ll pf1 = -999999999999999LL;ll pf2 = 0LL;
 while(n--){
 	ll a,b,c;cin>>a>>b>>c;a--;b--;
 	ll mx = -999999999999999LL;
 	if(mp1.count(a)){mx = max(mp1[a],mx);}
 	if(mp2.count(b)){mx = max(mp2[b],mx);}
 	if(mp3.count(a-b)){mx = max(mp3[a-b],mx);}
 	if(mp4.count(a+b)){mx = max(mp4[a+b],mx);}
 	mx = max(mx,pf1);
 	pf1 = max(pf1,pf2);
 	pf2 = c+mx;
 	if(mp.count(pair(a,b))){mp[pair(a,b)]=max(mp[pair(a,b)],c+mx);}
 	else{mp[pair(a,b)]=c+mx;}
 	if(mp1.count(a)){
 		mp1[a] = max(mp1[a],c+mx);
 	}
 	else{mp1[a]=c+mx;}
 	if(mp2.count(b)){
 		mp2[b] = max(mp2[b],c+mx);
 	}
 	else{mp2[b]=c+mx;}
 	if(mp3.count(a-b)){
 		mp3[a-b] = max(mp3[a-b],c+mx);
 	}
 	else{mp3[a-b]=c+mx;}
 	if(mp4.count(a+b)){
 		mp4[a+b] = max(mp4[a+b],c+mx);
 	}
 	else{mp4[a+b]=c+mx;}
 }
 ll ans = 0;
 for(auto u : mp){
 	ans = max(ans,u.second);
 }
 cout << ans << endl;
}