#include using namespace std; using int64 = long long; const int mod = 1e9 + 7; const int64 infll = (1LL << 62) - 1; const int inf = (1 << 30) - 1; struct IoSetup { IoSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(10); cerr << fixed << setprecision(10); } } iosetup; template< typename T1, typename T2 > ostream &operator<<(ostream &os, const pair< T1, T2 > &p) { os << p.first << " " << p.second; return os; } template< typename T1, typename T2 > istream &operator>>(istream &is, pair< T1, T2 > &p) { is >> p.first >> p.second; return is; } template< typename T > ostream &operator<<(ostream &os, const vector< T > &v) { for(int i = 0; i < (int) v.size(); i++) { os << v[i] << (i + 1 != v.size() ? " " : ""); } return os; } template< typename T > istream &operator>>(istream &is, vector< T > &v) { for(T &in : v) is >> in; return is; } template< typename T1, typename T2 > inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); } template< typename T1, typename T2 > inline bool chmin(T1 &a, T2 b) { return a > b && (a = b, true); } template< typename T = int64 > vector< T > make_v(size_t a) { return vector< T >(a); } template< typename T, typename... Ts > auto make_v(size_t a, Ts... ts) { return vector< decltype(make_v< T >(ts...)) >(a, make_v< T >(ts...)); } template< typename T, typename V > typename enable_if< is_class< T >::value == 0 >::type fill_v(T &t, const V &v) { t = v; } template< typename T, typename V > typename enable_if< is_class< T >::value != 0 >::type fill_v(T &t, const V &v) { for(auto &e : t) fill_v(e, v); } template< typename F > struct FixPoint : F { FixPoint(F &&f) : F(forward< F >(f)) {} template< typename... Args > decltype(auto) operator()(Args &&... args) const { return F::operator()(*this, forward< Args >(args)...); } }; template< typename F > inline decltype(auto) MFP(F &&f) { return FixPoint< F >{forward< F >(f)}; } int main() { int W, H, N; cin >> W >> H >> N; vector< int > X(N), Y(N), L(N); for(int i = 0; i < N; i++) { cin >> X[i] >> Y[i] >> L[i]; } map< int, int > mpSita, mpUe; map< int, int > mpMigi, mpHidari; for(int i = 0; i < N; i++) { if(Y[i] == 0) { mpSita[X[i]] += L[i]; int cash = mpSita[X[i]]; int64 times = infll; int type = -1; if(mpUe.count(X[i])) { if(mpUe[X[i]] <= cash) { if(chmin(times, mpUe[X[i]])) type = 0; } } for(auto &p : mpHidari) { if(p.first <= cash) { if(p.second >= X[i]) { if(chmin(times, p.first)) type = 1; } } } for(auto &p : mpMigi) { if(p.first <= cash) { if(p.second <= X[i]) { if(chmin(times, p.first)) type = 2; } } } if(H + 1 <= cash) { if(chmin(times, H + 1)) type = 3; } if(~type) { mpSita.erase(X[i]); if(type == 0) { mpUe.erase(X[i]); } else if(type == 1) { mpHidari.erase(times); } else if(type == 2) { mpMigi.erase(times); } } } else if(Y[i] == H + 1) { if(!mpUe.count(X[i])) mpUe[X[i]] = H + 1; mpUe[X[i]] -= L[i]; int cash = mpUe[X[i]]; int64 times = -infll; int type = -1; if(mpSita.count(X[i])) { if(mpSita[X[i]] >= cash) { if(chmax(times, mpSita[X[i]])) type = 0; } } for(auto &p : mpHidari) { if(p.first >= cash) { if(p.second >= X[i]) { if(chmax(times, p.first)) type = 1; } } } for(auto &p : mpMigi) { if(p.first >= cash) { if(p.second <= X[i]) { if(chmax(times, p.first)) type = 2; } } } if(cash <= 0) { if(chmax(times, 0)) type = 3; } if(~type) { mpUe.erase(X[i]); if(type == 0) { mpSita.erase(X[i]); } else if(type == 1) { mpHidari.erase(times); } else if(type == 2) { mpMigi.erase(times); } } } else if(X[i] == 0) { mpHidari[Y[i]] += L[i]; int cash = mpHidari[Y[i]]; int64 times = infll; int type = -1; if(mpMigi.count(Y[i])) { if(mpMigi[Y[i]] <= cash) { if(chmin(times, mpMigi[Y[i]])) type = 0; } } for(auto &p : mpUe) { if(p.first <= cash) { if(p.second <= Y[i]) { if(chmin(times, p.first)) type = 1; } } } for(auto &p : mpSita) { if(p.first <= cash) { if(p.second >= Y[i]) { if(chmin(times, p.first)) type = 2; } } } if(W + 1 <= cash) { if(chmin(times, W + 1)) type = 3; } if(~type) { mpHidari.erase(Y[i]); if(type == 0) { mpMigi.erase(Y[i]); } else if(type == 1) { mpUe.erase(times); } else if(type == 2) { mpSita.erase(times); } } } else if(X[i] == W + 1) { if(!mpMigi.count(Y[i])) mpMigi[Y[i]] = W + 1; mpMigi[Y[i]] -= L[i]; int cash = mpMigi[Y[i]]; int64 times = -infll; int type = -1; if(mpHidari.count(Y[i])) { if(mpHidari[Y[i]] >= cash) { if(chmax(times, mpHidari[Y[i]])) type = 0; } } for(auto &p : mpUe) { if(p.first >= cash) { if(p.second <= Y[i]) { if(chmax(times, p.first)) type = 1; } } } for(auto &p : mpSita) { if(p.first >= cash) { if(p.second >= Y[i]) { if(chmax(times, p.first)) type = 2; } } } if(cash <= 0) { if(chmax(times, 0)) type = 3; } if(~type) { mpMigi.erase(Y[i]); if(type == 0) { mpHidari.erase(Y[i]); } else if(type == 1) { mpUe.erase(times); } else if(type == 2) { mpSita.erase(times); } } } else { assert(0); } } int64 ret = 0; for(auto &p : mpUe) ret += H + 1 - p.second; for(auto &p : mpMigi) ret += W + 1 - p.second; for(auto &p : mpHidari) ret += p.second; for(auto &p : mpSita) ret += p.second; cout << ret << endl; }