solution-code4469
模板题,统计更改数目就是求总数目的变化量
#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>using namespace std;struct Node{ int to,next;}e[200005];struct Tree{ int L,R,lazy,sum;}T[400005];int siz[200005],d[200005],h[200005],pre[200005],vson[200005],pos[200005],top[200005],sign,cnt;inline void Addedge(int x,int y){ e[++cnt]=(Node){y,h[x]};h[x]=cnt;return;}inline void dfs1(int x,int dep){ int i,y; d[x]=dep;siz[x]=1; vson[x]=-1; for(i=h[x];i;i=e[i].next) { y=e[i].to; dfs1(y,dep+1); siz[x]+=siz[y]; if(vson[x]==-1||siz[vson[x]]<siz[y])vson[x]=y; } return;}inline void dfs2(int x,int sp){ int i,y; pos[x]=++sign;top[x]=sp; if(vson[x]!=-1)dfs2(vson[x],sp); for(i=h[x];i;i=e[i].next) { y=e[i].to; if(y==vson[x])continue; dfs2(y,y); } return;}inline void Build(int L,int R,int v){ T[v].L=L;T[v].R=R; T[v].lazy=-1; if(L==R)return; int mid=(L+R)>>1; Build(L,mid,v<<1); Build(mid+1,R,(v<<1)|1); return;}inline void pushdown(int v){ if(T[v].lazy==-1)return; T[v<<1].sum=(T[v<<1].R-T[v<<1].L+1)*T[v].lazy; T[(v<<1)|1].sum=(T[(v<<1)|1].R-T[(v<<1)|1].L+1)*T[v].lazy; T[v<<1].lazy=T[(v<<1)|1].lazy=T[v].lazy; T[v].lazy=-1; return;}inline void pushup(int v){ T[v].sum=T[v<<1].sum+T[(v<<1)|1].sum; return;}inline void Insert(int L,int R,int val,int v){ if(L>T[v].R||R<T[v].L)return; if(L<=T[v].L&&R>=T[v].R) { T[v].sum=(T[v].R-T[v].L+1)*val; T[v].lazy=val;return; } pushdown(v); Insert(L,R,val,v<<1); Insert(L,R,val,(v<<1)|1); pushup(v); return;}inline void Insert(int x,int y,int val){ while(top[x]!=top[y]) { if(d[top[x]]<d[top[y]])swap(x,y); Insert(pos[top[x]],pos[x],val,1); x=pre[top[x]]; } if(d[x]>d[y])swap(x,y); Insert(pos[x],pos[y],val,1); return;}char cmd[15];int main(void){ int i,n,m,x,lst; scanf("%d",&n); for(i=2;i<=n;++i) { scanf("%d",&pre[i]);++pre[i]; Addedge(pre[i],i); } dfs1(1,1); dfs2(1,1); Build(1,sign,1); scanf("%d",&m); for(i=1;i<=m;++i) { scanf("%s%d",cmd,&x);++x; lst=T[1].sum; if(strcmp(cmd,"install")==0) { Insert(1,x,1); printf("%d\n",T[1].sum-lst); } else { Insert(pos[x],pos[x]+siz[x]-1,0,1); printf("%d\n",lst-T[1].sum); } } return 0;}