非常不容易的一道题，把每个点向右上构造一个矩形，将问题转化为重合矩形那个亮度最大，注意LL，注意排序。
1 #include <cstdio> 2 #include <cstring> 3 #include <string> 4 #include <algorithm> 5 using namespace std; 6 #define maxn 50100 7 #define lson l,m,rt<<1 8 #define rson m+1,r,rt<<1|1 9 #define LL __int64 10 struct node 11 { 12 LL lx,rx,y; 13 LL s; 14 node(){} 15 node(LL a,LL b,LL c,LL d):lx(a),rx(b),y(c),s(d){} 16 bool operator < (const node &S) const 17 { 18 if(y == S.y) 19 return s > S.s; 20 else 21 return y < S.y; 22 } 23 }mat[maxn]; 24 LL que[2*maxn]; 25 LL tree[4*maxn]; 26 LL lz[4*maxn]; 27 void pushup(int rt) 28 { 29 tree[rt] = max(tree[rt<<1],tree[rt<<1|1]); 30 } 31 void pushdown(int rt) 32 { 33 if(lz[rt]) 34 { 35 lz[rt<<1] += lz[rt]; 36 lz[rt<<1|1] += lz[rt]; 37 tree[rt<<1] += lz[rt]; 38 tree[rt<<1|1] += lz[rt]; 39 lz[rt] = 0; 40 } 41 } 42 void update(int L,int R,int c,int l,int r,int rt) 43 { 44 int m; 45 if(L <= l&&r <= R) 46 { 47 tree[rt] += c; 48 lz[rt] += c; 49 return ; 50 } 51 pushdown(rt); 52 m = (l+r)>>1; 53 if(L <= m) 54 update(L,R,c,lson); 55 if(R > m) 56 update(L,R,c,rson); 57 pushup(rt); 58 } 59 int bin(LL x,int n) 60 { 61 int str,mid,end; 62 str = 0; 63 end = n; 64 while(str <= end) 65 { 66 mid = (str+end)/2; 67 if(que[mid] == x) 68 return mid; 69 else if(que[mid] > x) 70 end = mid - 1; 71 else 72 str = mid + 1; 73 } 74 return mid; 75 } 76 int main() 77 { 78 int n,num,k,i; 79 LL a,b,c,h,w; 80 while(scanf("%d%I64d%I64d",&n,&w,&h)!=EOF) 81 { 82 num = 0; 83 w--; 84 h--; 85 for(i = 0;i < n;i ++) 86 { 87 scanf("%I64d%I64d%I64d",&a,&b,&c); 88 mat[num] = node(a,a+w,b,c); 89 que[num++] = a; 90 mat[num] = node(a,a+w,b+h,-c); 91 que[num++] = a+w; 92 } 93 k = 1; 94 sort(que,que+num); 95 sort(mat,mat+num); 96 for(i = 1;i < num;i ++) 97 { 98 if(que[i] != que[i-1]) 99 que[k++] = que[i]; 100 } 101 LL maxz = 0; 102 memset(tree,0,sizeof(tree)); 103 memset(lz,0,sizeof(lz)); 104 for(i = 0;i < num;i ++) 105 { 106 int l = bin(mat[i].lx,k-1); 107 int r = bin(mat[i].rx,k-1); 108 if(l <= r) update(l,r,mat[i].s,0,k-1,1); 109 maxz = max(maxz,tree[1]); 110 } 111 printf("%I64d ",maxz); 112 } 113 return 0; 114 }