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【BZOJ2874】训练士兵(主席树)

2017-01-05 19:28 573 查看

题意:有一个N*M的矩阵,给出一些形如(x1,y1,x2,y2,s)的操作,代表(x1,y1)到(x2,y2)都被加上了s这个数

现在有一些强制在线的询问,询问(x1,y1)到(x2,y2)的和

对于100%的数据 n,m<=10^8,k<=40000,q<=100000; 

思路:将操作(x1,y1,x2,y2,s)差分成

(x1,y1)+s

(x1,y2+1)-s

(x2+1,y1)-s

(x2+1,y2+1)+s 

四个点

询问(x,y)等价于

\[\sum_{i=1}^x  \sum_{j=1}^y  \ a[i,j]*(x+1)*(y+1)-a[i,j]*i*(y+1)-a[i,j]*j*(x+1)+a[i,j]*i*j \]

证明如下:

可以看出只需维护a[i,j],a[i,j]*i,a[i,j]*j,a[i,j]*i*j四个值的二维前缀和

从左到右,从上到下排序并离散化,对每一行建立一棵主席树表示左上角的前缀和,

询问时在主席树中查找一段从头开始的前缀和即可

1 var t:array[0..6000000,1..6]of int64;
2     root:array[0..600000]of int64;
3     c:array[1..300000,1..3]of int64;
4     cx,cy:array[1..300000]of int64;
5     n,m,i,j,u,k,cnt,u1,u2,k1,q1,tmp,x,y:longint;
6     ans,x1,y1,x2,y2:int64;
7
8 procedure swap(var x,y:int64);
9 var t:int64;
10 begin
11  t:=x; x:=y; y:=t;
12 end;
13
14 procedure qsortx(l,r:longint);
15 var i,j,mid:longint;
16 begin
17  i:=l; j:=r; mid:=cx[(l+r)>>1];
18  repeat
19   while mid>cx[i] do inc(i);
20   while mid<cx[j] do dec(j);
21   if i<=j then
22   begin
23    swap(cx[i],cx[j]);
24    inc(i); dec(j);
25   end;
26  until i>j;
27  if l<j then qsortx(l,j);
28  if i<r then qsortx(i,r);
29 end;
30
31 procedure qsorty(l,r:longint);
32 var i,j,mid:longint;
33 begin
34  i:=l; j:=r; mid:=cy[(l+r)>>1];
35  repeat
36   while mid>cy[i] do inc(i);
37   while mid<cy[j] do dec(j);
38   if i<=j then
39   begin
40    swap(cy[i],cy[j]);
41    inc(i); dec(j);
42   end;
43  until i>j;
44  if l<j then qsorty(l,j);
45  if i<r then qsorty(i,r);
46 end;
47
48 function hashx(x:longint):longint;
49 var l,r,mid,last:longint;
50 begin
51  l:=1; r:=u1; last:=0;
52  while l<=r do
53  begin
54   mid:=(l+r)>>1;
55   if x>=cx[mid] then begin last:=mid; l:=mid+1; end
56    else r:=mid-1;
57  end;
58  exit(last);
59 end;
60
61 function hashy(x:longint):longint;
62 var l,r,mid,last:longint;
63 begin
64  l:=1; r:=u2; last:=0;
65  while l<=r do
66  begin
67   mid:=(l+r)>>1;
68   if x>=cy[mid] then begin last:=mid; l:=mid+1; end
69    else r:=mid-1;
70  end;
71  exit(last);
72 end;
73
74 procedure qsort(l,r:longint);
75 var i,j,mid1,mid2:longint;
76 begin
77  i:=l; j:=r; mid1:=c[(l+r)>>1,1]; mid2:=c[(l+r)>>1,2];
78  repeat
79   while (mid1>c[i,1])or((mid1=c[i,1])and(mid2>c[i,2])) do inc(i);
80   while (mid1<c[j,1])or((mid1=c[j,1])and(mid2<c[j,2])) do dec(j);
81   if i<=j then
82   begin
83    swap(c[i,1],c[j,1]);
84    swap(c[i,2],c[j,2]);
85    swap(c[i,3],c[j,3]);
86    inc(i); dec(j);
87   end;
88  until i>j;
89  if l<j then qsort(l,j);
90  if i<r then qsort(i,r);
91 end;
92
93 function query(p,l,r,x,y:longint):int64;
94 var mid:longint;
95 begin
96  if x=0 then exit(0);
97  if p=0 then exit(0);
98  if x>=r then exit(t[p,y]);
99  mid:=(l+r)>>1;
100  if x<=mid then exit(query(t[p,5],l,mid,x,y))
101   else exit(t[t[p,5],y]+query(t[p,6],mid+1,r,x,y));
102 end;
103
104 function ask(x,y:longint):int64;
105 var x1,y1:longint;
106 begin
107  x1:=hashx(x); y1:=hashy(y);
108  ask:=0;
109  ask:=ask+query(root[x1],1,u2,y1,1)*(x+1)*(y+1);
110  ask:=ask-query(root[x1],1,u2,y1,2)*(y+1);
111  ask:=ask-query(root[x1],1,u2,y1,3)*(x+1);
112  ask:=ask+query(root[x1],1,u2,y1,4);
113 end;
114
115 procedure update(var p:int64;l,r,x:longint;v:int64;x1,y1:longint);
116 var mid:longint;
117 begin
118  inc(cnt); t[cnt]:=t

; 119 p:=cnt; 120 t[cnt,1]:=t[cnt,1]+v; 121 t[cnt,2]:=t[cnt,2]+v*x1; 122 t[cnt,3]:=t[cnt,3]+v*y1; 123 t[cnt,4]:=t[cnt,4]+v*x1*y1; 124 if l=r then exit; 125 mid:=(l+r)>>1; 126 if x<=mid then update(t[p,5],l,mid,x,v,x1,y1) 127 else update(t[p,6],mid+1,r,x,v,x1,y1); 128 end; 129 130 begin 131 assign(input,'bzoj2874.in'); reset(input); 132 assign(output,'bzoj2874.out'); rewrite(output); 133 readln(n,m,k1,q1); 134 k:=0; 135 for i:=1 to k1 do 136 begin 137 read(x1); read(x2); read(y1); read(y2); read(tmp); 138 inc(k); c[k,1]:=x1; c[k,2]:=y1; c[k,3]:=tmp; 139 inc(k); c[k,1]:=x1; c[k,2]:=y2+1; c[k,3]:=-tmp; 140 inc(k); c[k,1]:=x2+1; c[k,2]:=y1; c[k,3]:=-tmp; 141 inc(k); c[k,1]:=x2+1; c[k,2]:=y2+1; c[k,3]:=tmp; 142 inc(u); cx[u]:=x1; cy[u]:=y1; 143 inc(u); cx[u]:=x2+1; cy[u]:=y2+1; 144 end; 145 qsortx(1,u); qsorty(1,u); 146 u1:=1; 147 for i:=2 to u do 148 if cx[i]<>cx[u1] then begin inc(u1); cx[u1]:=cx[i]; end; 149 u2:=1; 150 for i:=2 to u do 151 if cy[i]<>cy[u2] then begin inc(u2); cy[u2]:=cy[i]; end; 152 153 qsort(1,k); 154 j:=1; 155 for i:=1 to u1 do 156 begin 157 root[i]:=root[i-1]; 158 while (j<=k)and(hashx(c[j,1])=i) do 159 begin 160 update(root[i],1,u2,hashy(c[j,2]),c[j,3],c[j,1],c[j,2]); 161 inc(j); 162 end; 163 end; 164 for i:=1 to q1 do 165 begin 166 readln(x,y); 167 x1:=ans mod n+1; x2:=(ans+x) mod n+1; if x1>x2 then swap(x1,x2); 168 y1:=ans mod m+1; y2:=(ans+y) mod m+1; if y1>y2 then swap(y1,y2); 169 ans:=ask(x2,y2)-ask(x1-1,y2)-ask(x2,y1-1)+ask(x1-1,y1-1); 170 writeln(ans); 171 end; 172 close(input); 173 close(output); 174 end.

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