1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<queue>
#include<map>
#include<stack>
#include<set>
#include<bitset>
#include<cmath>
#include<assert.h>
#define inc(i,l,r) for(int i=l;i<=r;i++)
#define dec(i,l,r) for(int i=l;i>=r;i--)
#define link(x) for(edge *j=h[x];j;j=j->next)
#define mem(a) memset(a,0,sizeof(a))
#define ll unsigned long long
#define succ(x) (1ll<<x)
#define lowbit(x) (x&(-x))
#define sqr(x) ((x)*(x))
#define mid (x+y>>1)
#define NM 100005
#define nm 400005
using namespace std;
const double pi=acos(-1);
const int inf=1e9+9;
const double eps=1e-8;
ll read(){
ll x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
return f*x;
}
int n,_x,_y,b[NM],ans,c[NM],tot;
struct P{
int x,y,v;
bool operator<(const P&o)const{return x<o.x||(x==o.x&&y>o.y);}
}a[NM];
inline void add(int x,int t){for(;x<=tot;x+=lowbit(x))c[x]=max(c[x],t);}
inline int sum(int x,int s=0){for(;x;x-=lowbit(x))s=max(s,c[x]);return s;}
int main(){
read();n=read();
inc(i,1,n){
_x=read();_y=read();a[i].v=read();
a[i].x=2*_x-_y;
a[i].y=2*_x+_y;
}
sort(a+1,a+1+n);
inc(i,1,n)b[i]=a[i].y;
sort(b+1,b+1+n);tot=unique(b+1,b+1+n)-b-1;
inc(i,1,n)a[i].y=lower_bound(b+1,b+1+tot,a[i].y)-b;
inc(i,1,n){
int t=sum(a[i].y)+a[i].v;
add(a[i].y,t);
ans=max(ans,t);
}
printf("%d\n",ans);
return 0;
}
|
