BZOJ 1062 糖果雨

http://www.lydsy.com/JudgeOnline/problem.php?id=1062

思路:找到平行四边形以后,变换坐标:y->y-kx,k为斜率,这样变成了矩形,然后只要二维树状数组就行了、

注意可能因为取余的原因,把一个平行四边形拆成两半

 1 #include<algorithm>
 2 #include<cstdio>
 3 #include<cmath>
 4 #include<cstring>
 5 #include<iostream>
 6 int len2,len,len4,n;
 7 int tr[2][2005][4005];
 8 int x[4000005],y[4000005];
 9 int lowbit(int X){
10     return (X)&(-X);
11 }
12 int read(){
13     int t=0,f=1;char ch=getchar();
14     while (ch<'0'||ch>'9'){if (ch=='-') f=-1;ch=getchar();}
15     while ('0'<=ch&&ch<='9'){t=t*10+ch-'0';ch=getchar();}
16     return t*f;
17 }
18 void add(int k,int x,int y,int c){
19     x++;y++;
20     for (int i=x;i<=len2;i+=lowbit(i))
21      for (int j=y;j<=len4;j+=lowbit(j))
22       tr[k][i][j]+=c;
23 }
24 int sum(int k,int x,int y){
25     if (x<0||y<0) return 0;
26     x++;y++;
27     int ans=0;
28     if (x>len2) x=len2+1;
29     if (y>len4) y=len4+1;
30     for (int i=x;i;i-=lowbit(i))
31      for (int j=y;j;j-=lowbit(j))
32       ans+=tr[k][i][j];
33     return ans;  
34 }
35 int sum(int k,int x1,int y1,int x2,int y2){
36     return sum(k,x2,y2)+sum(k,x1-1,y1-1)-sum(k,x2,y1-1)-sum(k,x1-1,y2);
37 }
38 int main(){
39     n=read();len=read();len2=len<<1;len4=len2<<1;
40     while (n--){
41         int opt=read();
42         if (opt==1){
43             int t=read(),c=read(),l=read(),r=read(),d=read();
44             x[c]=(t-d*l+len2)%len2;
45             y[c]=r-l;
46             add(0,x[c],y[c]+x[c],1);
47             add(1,x[c],y[c]-x[c]+len2,1);
48         }else
49         if (opt==2)
50         {
51             int t=read(),l=read(),r=read();
52             t%=len2;
53             int k=(r==len);
54             int ans=sum(0,t,l+t,r+t,len4)+sum(0,0,l+t-len2,r+t-len2-k,len4)
55             +sum(1,t-r+len2+k,l-t,len2,len4)+sum(1,t-r,l-t+len2,t-1,len4);
56             printf("%d\n",ans);
57         }else{
58             int t=read(),c=read();
59             add(0,x[c],y[c]+x[c],-1);
60             add(1,x[c],y[c]-x[c]+len2,-1);
61         }
62     }
63     
64 }

 

posted @ 2016-06-20 19:21  GFY  阅读(313)  评论(0编辑  收藏  举报