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#include <bits/stdc++.h>

using namespace std;
using ll = long long;
#define int ll
using PII = pair<int, int>;
template <typename T> using V = vector<T>;
template <typename T> using VV = vector<V<T>>;
template <typename T> using VVV = vector<VV<T>>;

#define FOR(i, a, n) for (ll i = (ll)a; i < (ll)n; ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(x) x.begin(), x.end()
#define PB push_back

const ll INF = (1LL<<60);
const int MOD = 1000000007;

template <typename T> T &chmin(T &a, const T &b) { return a = min(a, b); }
template <typename T> T &chmax(T &a, const T &b) { return a = max(a, b); }
template <typename T> bool IN(T a, T b, T x) { return a<=x&&x<b; }
template<typename T> T ceil(T a, T b) { return a/b + !!(a%b); }
template<class S,class T>
ostream &operator <<(ostream& out,const pair<S,T>& a){
  out<<'('<<a.first<<','<<a.second<<')';
  return out;
}
template<class T>
ostream &operator <<(ostream& out,const vector<T>& a){
  out<<'[';
  REP(i, a.size()) {out<<a[i];if(i!=a.size()-1)out<<',';}
  out<<']';
  return out;
}

int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0};

signed main(void)
{
  cin.tie(0);
  ios::sync_with_stdio(false);

  int n, m;
  cin >> n >> m;
  V<int> a(m), b(m), x(m);
  REP(i, m) cin >> a[i] >> b[i] >> x[i], a[i]--, b[i]--;

  VV<int> board(n+5, V<int>(n+5));
  REP(i, m) {
    board[a[i]][b[i]]++;
    board[a[i]+x[i]+1][b[i]]--;
    board[a[i]][b[i]+1]--;
    board[a[i]+x[i]+2][b[i]+1]++;
    board[a[i]+x[i]+1][b[i]+x[i]+2]++;
    board[a[i]+x[i]+2][b[i]+x[i]+2]--;
  }

  FOR(i, 1, n+5) REP(j, n+5) {
    board[i][j] += board[i-1][j];
  }
  FOR(i, 1, n+5) REP(j, n+5) {
    board[j][i] += board[j][i-1];
  }
  FOR(i, 1, n) {
    for(int tx=1, ty=i; tx<n+5&&ty<n+5; ++tx, ++ty) {
      board[ty][tx] += board[ty-1][tx-1];
    }
  }
  
  int ret = 0;
  REP(i, n) REP(j, n) {
    if(board[i][j] > 0) ret++;
  }
  cout << ret << endl;

  return 0;
}