poj1195 二维树状数组【pascal】

二维树状数组模板=。=

var
tt,n,x,y,l,b,r,t,z:longint;
i,j :longint;
c :array[0..1025,0..1025] of longint;
function lowbit(x:longint):Longint;
begin
exit(x and (-x));
end;

procedure add(x,y,z:longint);
var
t1,t2:longint;
begin
while (x<=n) do
begin
t1:=y;
while (t1<=n) do
begin
inc(c[x,t1],z);
inc(t1,lowbit(t1));
end;
inc(x,lowbit(x));
end;

end;

function sum(x,y:longint):longint;
var
ans,y1:longint;
begin
ans:=0;
while (x>0) do
begin
y1:=y;
while (y1>0) do
begin
inc(ans,c[x,y1]);
dec(y1,lowbit(y1));
end;
dec(x,lowbit(x));
end;
exit(ans);
end;

function find(l,b,r,t:longint):Longint;
begin
exit(sum(r,t)-sum(l-1,t)-sum(r,b-1)+sum(l-1,b-1));
end;

begin
read(tt);
while (tt<>3) do
begin
if (tt=0) then
begin
read(n);
fillchar(c,sizeof(c),0);
end else
if (tt=1) then
begin
read(x,y,z);
inc(x);inc(y);
add(x,y,z);
end else
if (tt=2) then
begin
read(l,b,r,t);
inc(l);inc(b);inc(r);inc(t);
writeln(find(l,b,r,t));
end;
read(tt);
end;
end.
——by Eirlys