HDU 1540 Tunnel Warfare

Title Link: http://acm.hdu.edu.cn/showproblem.php?pid=1540

To give you a row of consecutive points, you can do the following three kinds of operations:

1. Delete a point

2, inquiry and length of the segment of a point (if the point has been deleted, the length is 0)

3. Restore the last deleted point

The segment tree calculates a continuous interval, and the node holds the left continuous length LM, and the right continuous length of RM

1 /*2 * Problem:hdu 1540 tunnel Warfare3 * AUTHOR:SHJWUDP4 * Created time:2015/3/28 Saturday 13:10:495 * File name:233.cpp6 * state:accepted7 * Memo: Line tree8  */9#include <iostream>Ten#include <cstdio> One#include <cstring> A#include <algorithm> -  - using namespacestd; the  - Const intmaxa=5e4+7; -  - structSegmenttree { + //This structure can be used to find the maximum continuous interval, only one variable is needed to save the maximum continuous interval under the current node. -     structNode { +         intLM, RM; A Node () {} atNode (intLintr): LM (L), RM (r) {} -} *C; -     intN; -     intp, sign; -  -Segmenttree (intN): N (n) { inC=Newnode[(n+7) <<2]; -Build1N1); to     } +~Segmenttree () { -         DeleteC; the     } * #defineINIT node& U=c[rt]; node& ls=c[rt<<1]; node& rs=c[rt<<1|1]; $ #defineLson L, M, rt<<1Panax Notoginseng #defineRson m+1, R, rt<<1|1 -  the     voidPushup (intLintMintRintRT) { + INIT; Au=Node (LS.LM, rs.rm); the         if(m-l+1==LS.LM) u.lm+=rs.lm; +         if(R-M==RS.RM) u.rm+=ls.rm; -     } $  $     voidBuildintLintRintRT) { -         if(l==r) { -C[rt]=node (1,1); the}Else { -             intM= (l+r) >>1;Wuyi build (Lson); the build (Rson); - pushup (L, M, R, RT); Wu         } -     } About  $     voidDoUpdate (intLintRintRT) { -         if(l==r) { -C[rt]=sign? Node (1,1): Node (0,0); -}Else { A             intM= (l+r) >>1; +             if(p<=m) doupdate (Lson); the             Elsedoupdate (Rson); - pushup (L, M, R, RT); $         } the     } the  the     voidUpdateintPintSign ) { the          This->p=p; This->sign=Sign ; -DoUpdate (1N1); in     } the  the     intDoquery (intLintRintRT) { About INIT; the         if(P-L&LT;U.LM | | r-p<u.rm) { the             returnP-l<u.lm?u.lm:u.rm; the}Else if(L==R)return 0; +         Else { -             intM= (l+r) >>1; the             intres=0;Bayi             if(p<=m) Res+=doquery (Lson) + (m-p+1&LT;=LS.RM?RS.LM:0); the             ElseRes+=doquery (Rson) + (p-m<=rs.lm?ls.rm:0); the             returnRes; -         } -     } the  the     intQueryintp) { the          This->p=p; the         returnDoquery (1N1); -     } the #undefInit the #undefLson the #undefRson94 }; the  the intN, M; the intStk[maxa], top;98 intMain () { About #ifndef Online_judge -Freopen ("inch","R", stdin);101     //freopen ("Out", "w", stdout);102 #endif103      while(~SCANF ("%d%d", &n, &m)) {104 Segmenttree St (n); thetop=0;106          while(m--) {107             Charop[2];108             intx;109scanf"%s", op); the             Switch(op[0]) {111              Case 'D':  thescanf"%d", &x);113St.update (Stk[++top]=x,0); the                  Break; the              Case 'Q':  thescanf"%d", &x);117printf"%d\n", St.query (x));118                  Break;119              Case 'R':  -St.update (stk[top--],1);121                  Break;122             }123         }124     } the     return 0;126}

HDU 1540

HDU 1540 Tunnel Warfare