#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define make_unique(x) sort(all(x)), x.erase(unique(all(x)), x.end())
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 Rng(chrono::steady_clock::now().time_since_epoch().count());
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
const int N = 1e5 + 200;
const int M = 1e5;
const int inf = 2e9 + 3;
const ll INF = 1e18;
int n, m, k;
long long X[101], Y[101], R[101];
int main() {
cin.tie(0)->sync_with_stdio(0);
cin >> n >> m;
cin >> k;
for (int i = 1; i <= k; ++i) {
cin >> X[i] >> Y[i] >> R[i];
}
long long sum = 0;
int mx = 0;
for (int x = 1; x <= n; ++x) {
vector<pair<pair<int, int>, int>> v = {{{1, m}, 0}};
for (int i = 1; i <= k; ++i) {
long long D = R[i] * R[i] - (x - X[i]) * (x - X[i]);
if (D < 0) {
continue;
}
int l = Y[i] - (floor(sqrt(D)));
int r = Y[i] + (floor(sqrt(D)));
vector<pair<pair<int, int>, int>> nv;
mx = max(mx, sz(v));
for (auto p : v) {
if (p.F.F < l && r < p.F.S) {
nv.push_back({{p.F.F, l-1}, p.S});
nv.push_back({{r+1, p.F.S}, p.S});
continue;
}
if (p.F.S < l) {
nv.push_back(p);
continue;
}
if (p.F.F < l && l <= p.F.S) {
nv.push_back({{p.F.F, l-1}, p.S});
continue;
}
if (p.F.F <= r && r < p.F.S) {
nv.push_back({{r+1, p.F.S}, p.S});
continue;
}
if (p.F.F > r) {
nv.push_back(p);
continue;
}
}
nv.push_back({{l, r}, i});
v = nv;
}
for (auto p : v) {
sum += (k - p.S) * 1ll * (p.F.S - p.F.F + 1);
}
}
assert(mx <= 60);
cout << sum << '\n';
}
