Tree array (Template)

One-dimensional and two-dimensional templates of tree Arrays

Template

 Int Lowbit ( Int X)
{
 Return X & (-x );
}
 Void Modify ( Int X, Int Add) //  One-dimensional  
 {
 While (X <= maxn)
{
A [x] + = add;
X + = lowbit (X );
}
}
 Int Get_sum ( Int X)
{
 Int Ret = 0 ;
 While (X! = 0 )
{
RET + = A [x];
X-= lowbit (X );
}
Return RET;
}
 Void Modify ( Int X, Int Y, Int Data) //  Two-dimensional  
 {
 For ( Int I = x; I <maxn; I + = lowbit (I ))
 For ( Int J = y; j <maxn; j + = lowbit (j ))
A [I] [J] + = data;
}
 Int Get_sum ( Int X, Int Y)
{
 Int Res = 0 ;
 For ( Int I = x; I> 0 ; I-= lowbit (I ))
 For ( Int J = y; j> 0 ; J-= lowbit (j ))
Res + = A [I] [J];
 Return Res;
}

Typical template questions

Hdu1166 one-dimensional deployment:

View code

# Include <stdio. h>
# Include < String . H>
# Include <stdlib. h>
 Int C [ 50011 ], N;
 Int Lowbit ( Int X) // Calculate lowbit  
 {
 Return X & (-x );
}
 Void Add ( Int I, Int Val) //  Change element I to Val  
 {
 While (I <= N)
{
C [I] + = val;
I + = lowbit (I );
}
}
 Int Sum ( Int I) //  Calculate the sum of the first I and  
 {
 Int S = 0 ;
 While (I> 0 )
{
S + = C [I];
I-= lowbit (I );
}
 Return S;
}
 Int Main ()
{
 Int I, j = 0 , A, B, V, T, num;
 Char STR [] = "  Add  " , Str1 [] = "  Sub  " , Str2 [] = "  End  " , Sub1 [ 6 ];

Scanf ( "  % D  " , & T );
 While (T --)
{
Scanf ( "  % D  " , & N );
Printf ( "  Case % d: \ n  " , ++ J );
Memset (C, 0 ,Sizeof (C ));
 For (I = 1 ; I <= N; ++ I)
{
Scanf ( "  % D  " , & V );
Add (I, V );
}
 While ( 1 )
{
Scanf ( "  % S " , Sub1 );
 If (! Strcmp (str2, sub1 ))
 Break ;
 If (! Strcmp (sub1, STR ))
{
Scanf ( "  % D  " , & A, & B );
Add (A, B );
}
 Else   If (! Strcmp (sub1, str1 ))
{
Scanf ("  % D  " , & A, & B );
Add (A,-B );
}
 Else {
Scanf ( "  % D  " , & A, & B );
Printf ( "  % D \ n  " , Sum (B)-sum (- 1 ));
}
}
}
 Return   0 ;
}

 

Hdu2642 stars two-dimensional:

View code

# Include <iostream>
# Include <algorithm>
 Using   Namespace STD;
 Const   Int Maxn = 1010 ;
 Int A [maxn] [maxn];
 Bool B [maxn] [maxn];
 Int Lowbit ( Int X)
{
 Return X & (-x );
}
 Void Modify ( Int X, Int Y, Int Data)
{
 For ( Int I = x; I <maxn; I + = lowbit (I ))
 For (Int J = y; j <maxn; j + = lowbit (j ))
A [I] [J] + = data;
}
 Int Get_sum ( Int X, Int Y)
{
 Int Res = 0 ;
 For ( Int I = x; I> 0 ; I-= lowbit (I ))
 For (Int J = y; j> 0 ; J-= lowbit (j ))
Res + = A [I] [J];
 Return Res;
}
 Int Main ()
{
 Int N, x, y, X1, Y1;
 Char STR [ 2 ];
Scanf ( "  % D  " , & N );
Memset (, 0 , Sizeof ());
Memset (B, False , Sizeof (B ));
 While (N --)
{
Scanf ( "  % S  " , STR );
 If (STR [ 0 ] = '  B ' )
{
Scanf ( "  % D  " , & X, & Y );
X ++; y ++;
 If (B [x] [Y]) Continue ;
Modify (x, y, 1 );
B [x] [Y] = True ;
}
 Else   If (STR [ 0 ] = '  D  ' )
{
Scanf ( "  % D  " , & X, & Y );
X ++; y ++;
 If (! B [x] [Y]) Continue ;
Modify (X, Y ,- 1 );
B [x] [Y] =False ;
}
 Else {
Scanf ( "  % D  " , & X, & X1, & Y, & Y1 );
X ++, y ++;
X1 ++, Y1 ++;
 If (X> X1) Swap (x, X1 );
 If (Y> Y1) Swap (Y, Y1 );
 Int Ans = get_sum (x1, Y1)-get_sum (X- 1 , Y1)-get_sum (x1, y-1 ) + Get_sum (X- 1 , Y- 1 );
Printf ( "  % D \ n  " , ANS );
}
}
 Return   0 ;
}