"BZOJ-1218" laser bomb prefixes and + enumerations

1218: [HNOI2003] Laser bomb time limit:10 Sec Memory limit:162 MB
submit:1778 solved:833
[Submit] [Status] [Discuss] Description

A new type of laser bomb that can destroy all the targets within a square with a side length of R. There are now N (n<=10000) targets on the map, with an integer xi,yi (whose value in [0,5000]) represents the position of the target on the map, each of which has a value. Laser bombs are placed through satellite positioning, but there is a drawback, is its scope of blasting, that is, the side of the R-side of the square must be parallel to the X, Y axis. If the target is on the edge of the blasting square, the target will not be destroyed. 0

Input

The first behavior of the input file is a positive integer n and a positive integer r, and the next n rows have 3 positive integers per line, respectively, representing

Output

The output file has only a positive integer, which means that a bomb can blow up a target with a maximum amount of value on the map (no more than 32767 results).

Sample Input2 1
0 0 1
1 1 1Sample Output1Hintsourcesolution

Noip2015day2t1 both visual sense

prefix and handle it, casually enumerate

Code

#include <iostream>#include<cstdio>#include<cmath>#include<cstring>#include<algorithm>using namespacestd;intRead () {intx=0, f=1;CharCh=GetChar ();  while(ch<'0'|| Ch>'9') {if(ch=='-') f=-1; Ch=GetChar ();}  while(ch>='0'&& ch<='9') {x=x*Ten+ch-'0'; Ch=GetChar ();} returnx*F;}intn,r,maxx,maxy,ans,sum[5010][5010];intMain () {n=read (), r=read ();  for(intX,y,w,i=1; i<=n; i++) x=read () +1, Y=read () +1, W=read (), Maxx=max (X,maxx), Maxy=max (maxy,y), sum[x][y]=W;  for(intI=1; i<=5001; i++)         for(intj=1; j<=5001; J + +) Sum[i][j]+=sum[i-1][j]+sum[i][j-1]-sum[i-1][j-1];  for(intk=0; i<=5001; i++)         for(intJ=r; j<=5001; J + +) ans=max (sum[i][j]-sum[i-r][j]-sum[i][j-r]+sum[i-r][j-R],ans); printf ("%d\n", ans); return 0;}

This JB question, the beginning of the hand of one of the 5001 dozen into 5000 has not been found, mdzz

Dcrusher always give me a water problem .

"BZOJ-1218" laser bomb prefixes and + enumerations