【Java每日一题，前缀和】天上的星星

package week2;
import java.util.Scanner;
/**
 * @author liangyuanshao
 * @date 2022/4/30 - 14:49
 */
public class Main {
  public static void main(String[] args) {
    Scanner s=new Scanner(System.in);
    int[][] arr=new int[2002][2002];
    int n=s.nextInt();
    for(int i=0;i<n;i++){
      arr[s.nextInt()+1][s.nextInt()+1]+=s.nextInt();
    }
    for(int i=1;i<=2001;i++){
      for(int j=1;j<=2001;j++){
        arr[i][j]=arr[i][j]+arr[i-1][j]+arr[i][j-1]-arr[i-1][j-1];
      }
    }
    int k=s.nextInt();
    while (k--!=0){
      int x1=s.nextInt(),y1=s.nextInt(),x2=s.nextInt(),y2=s.nextInt();
      System.out.println(arr[x2+1][y2+1]-arr[x2+1][y1]-arr[x1][y2+1]+arr[x1][y1]);
    }
  }
}