#include<bits/stdc++.h> using namespace std; int n,m,x,y,r,ans,tot; int a[3005][3005]; signed main(){ //freopen(".in","r",stdin); //freopen(".out","w",stdout); cin>>n>>m; for(int k=1;k<=m;k++){ cin>>x>>y>>r; for(int i=max(1,x-r);i<=min(n,x+r);i++){ a[i][max(1,y-r+abs(x-i))]++; a[i][min(n+1,y+r-abs(x-i)+1)]--; } } for(int i=1;i<=n;i++){ tot=0; for(int j=1;j<=n;j++){ tot+=a[i][j]; if(tot%2==1) ans++; } } cout<<ans; return 0; }