1 #include<cstdio>
2 #include<cstring>
3 #include<algorithm>
4 #define MAXN 20010
5 typedef __int64 LL;
6 using namespace std;
7 struct Seg
8 {
9 LL left,right,val,high;
10 friend bool operator<(Seg a,Seg b)
11 {
12 if(a.high!=b.high)
13 return a.high<b.high;
14 return a.val<b.val;
15 }
16 };
17 struct node
18 {
19 LL lazy,big;
20 };
21 Seg p[MAXN];
22 node tree[MAXN<<2];
23 LL X[MAXN];
24 inline void PushDown(int rt)
25 {
26 if(tree[rt].lazy)
27 {
28 tree[rt<<1].lazy+=tree[rt].lazy;
29 tree[rt<<1|1].lazy+=tree[rt].lazy;
30 tree[rt<<1].big+=tree[rt].lazy;
31 tree[rt<<1|1].big+=tree[rt].lazy;
32 tree[rt].lazy=0;
33 }
34 }
35 inline void PushUp(int rt)
36 {
37 tree[rt].big=max(tree[rt<<1].big,tree[rt<<1|1].big);
38 }
39 void Update(int x,int y,int val,int L,int R,int rt)
40 {
41 if(x<=L&&R<=y)
42 {
43 tree[rt].big+=val;
44 tree[rt].lazy+=val;
45 }
46 else
47 {
48 int mid=(L+R)>>1;
49 PushDown(rt);
50 if(x<=mid)
51 Update(x,y,val,L,mid,rt<<1);
52 if(y>mid)
53 Update(x,y,val,mid+1,R,rt<<1|1);
54 PushUp(rt);
55 }
56 }
57 int main()
58 {
59 int i,n,cnt;
60 LL w,h,x,y,c,ans;
61 while(~scanf("%d%I64d%I64d",&n,&w,&h))
62 {
63 for(i=cnt=0;i<n;i++)
64 {
65 scanf("%I64d%I64d%I64d",&x,&y,&c);
66 p[cnt].left=x;
67 p[cnt].right=x+w;
68 p[cnt].high=y;
69 p[cnt].val=c;
70 X[cnt++]=x;
71 p[cnt].left=x;
72 p[cnt].right=x+w;
73 p[cnt].high=y+h;
74 p[cnt].val=-c;
75 X[cnt++]=x+w;
76 }
77 sort(X,X+cnt);
78 sort(p,p+cnt);
79 n=unique(X,X+cnt)-X;
80 memset(tree,0,sizeof(tree));
81 for(ans=i=0;i<cnt;i++)
82 {
83 x=lower_bound(X,X+n,p[i].left)-X;
84 y=lower_bound(X,X+n,p[i].right)-X;
85 Update(x,y-1,p[i].val,0,n-2,1);
86 ans=max(ans,tree[1].big);
87 }
88 printf("%I64d\n",ans);
89 }
90 return 0;
91 }
