【SPOJ】4487 Can you answer these queries VI 【splay】

传送门：【SPOJ】4487 Can you answer these queries VI

题目分析：好久没写splay了。。不过写起来一点也不手生，还有就是这题并不能有空段，也就是至少要一个元素，我就是坑在这点上了。其他没坑点了。

这代码我写出来的第一感觉就是：就这么长？

代码如下：

#include <cstdio>#include <cstring>#include <algorithm>using namespace std ;typedef long long LL ;#define travel( e , H , u ) for ( Edge* e = H[u] ; e ; e = e -> next )#define rep( i , a , b ) for ( int i = ( a ) ; i <  ( b ) ; ++ i )#define rev( i , a , b ) for ( int i = ( a ) ; i >= ( b ) ; -- i )#define FOR( i , a , b ) for ( int i = ( a ) ; i <= ( b ) ; ++ i )#define clr( a , x ) memset ( a , x , sizeof a )#define cpy( a , x ) memcpy ( a , x , sizeof a )const int MAXN = 200005 ;const int INF = 0x3f3f3f3f ;struct SplayNode {int v ;int s ;int sum ;int Lmax ;int Rmax ;int maxSum ;SplayNode* f ;SplayNode* c[2] ;void clear () {v = sum = s = 0 ;Lmax = Rmax = maxSum = -INF ;}void up () {s = c[0] -> s + c[1] -> s + 1 ;sum = c[0] -> sum + v + c[1] -> sum ;Lmax = max ( c[0] -> Lmax , c[0] -> sum + v + max ( 0 , c[1] -> Lmax ) ) ;Rmax = max ( c[1] -> Rmax , c[1] -> sum + v + max ( 0 , c[0] -> Rmax ) ) ;maxSum = max ( max ( c[0] -> maxSum , c[1] -> maxSum ) , max ( 0 , c[0] -> Rmax ) + v + max ( 0 , c[1] -> Lmax ) ) ;}} Tnull , *null = &Tnull ;struct Splay {SplayNode node[MAXN] ;SplayNode* root ;SplayNode* cur ;Splay () : root ( null ) , cur ( node ) {}void clear () {null -> clear () ;root = null ;cur = node ;}SplayNode* newnode ( int v , SplayNode* f ) {cur -> v = cur -> sum = cur -> Lmax = cur -> Rmax = cur -> maxSum = v ;cur -> c[0] = cur -> c[1] = null ;cur -> s = 1 ;cur -> f = f ;return cur ++ ;}void build ( int n ) {clear () ;FOR ( i , 0 , n + 1 ) {int x = -INF ;if ( i >= 1 && i <= n ) scanf ( "%d" , &x ) ;SplayNode* o = newnode ( x , null ) ;o -> c[0] = root ;root -> f = o ;root = o ;root -> up () ;}}void rotate ( SplayNode* o , bool d ) {SplayNode* p = o -> f ;p -> c[!d] = o -> c[d] ;o -> c[d] -> f = p ;o -> f = p -> f ;if ( p -> f != null ) {if ( p == p -> f -> c[0] ) p -> f -> c[0] = o ;else                       p -> f -> c[1] = o ;}o -> c[d] = p ;p -> f = o ;p -> up () ;if ( root == p ) root = o ;}void splay ( SplayNode* o , SplayNode* f ) {while ( o -> f != f ) {SplayNode* p = o -> f ;if ( p -> f == f ) {if ( o == p -> c[0] ) rotate ( o , 1 ) ;else                  rotate ( o , 0 ) ;} else {if ( p == p -> f -> c[0] ) {if ( o == p -> c[0] ) rotate ( p , 1 ) , rotate ( o , 1 ) ;else                  rotate ( o , 0 ) , rotate ( o , 1 ) ;} else {if ( o == p -> c[1] ) rotate ( p , 0 ) , rotate ( o , 0 ) ;else                  rotate ( o , 1 ) , rotate ( o , 0 ) ;}}}o -> up () ;}void select ( int k , SplayNode* f ) {SplayNode* o = root ;++ k ;while ( o != null ) {int s = o -> c[0] -> s ;if ( k == s + 1 ) break ;if ( k <= s ) o = o -> c[0] ;else {k -= s + 1 ;o = o -> c[1] ;}}splay ( o , f ) ;}SplayNode* get ( int l , int r ) {select ( l - 1 , null ) ;select ( r + 1 , root ) ;return root -> c[1] -> c[0] ;}void remove ( int pos ) {get ( pos , pos ) ;root -> c[1] -> c[0] = null ;root -> c[1] -> up () ;root -> up () ;}void insert ( int pos , int v ) {get ( pos , pos - 1 ) ;//between x - 1 to xSplayNode* o = newnode ( v , root -> c[1] ) ;root -> c[1] -> c[0] = o ;root -> c[1] -> up () ;root -> up () ;splay ( o , null ) ;}void replace ( int pos , int v ) {select ( pos , null ) ;root -> v = v ;root -> up () ;}int query ( int L , int R ) {SplayNode* o = get ( L , R ) ;return o -> maxSum ;}} T ;int n , q ;void solve () {char op ;int x , y ;T.build ( n ) ;scanf ( "%d" , &q ) ;while ( q -- ) {scanf ( " %c" , &op ) ;if ( op == 'I' ) {scanf ( "%d%d" , &x , &y ) ;T.insert ( x , y ) ;} else if ( op == 'D' ) {scanf ( "%d" , &x ) ;T.remove ( x ) ;} else if ( op == 'R' ) {scanf ( "%d%d" , &x , &y ) ;T.replace ( x , y ) ;} else {scanf ( "%d%d" , &x , &y ) ;printf ( "%d\n" , T.query ( x , y ) ) ;}}}int main () {while ( ~scanf ( "%d" , &n ) ) solve () ;return 0 ;}