【BZOJ】【2819】NIM

  1 //BZOJ 2819
  2 #include<cstdio>
  3 #include<vector>
  4 #include<cstring>
  5 #include<cstdlib>
  6 #include<iostream>
  7 #include<algorithm>
  8 #define rep(i,n) for(int i=0;i<n;++i)
  9 #define F(i,j,n) for(int i=j;i<=n;++i)
 10 #define D(i,j,n) for(int i=j;i>=n;--i)
 11 #define pb push_back
 12 using namespace std;
 13 const int N=500010;
 14 #define debug
 15 int n,a[N],t[N<<2],fa[N],top[N],dep[N],son[N],size[N],tid[N],cnt=0;
 16 vector<int>G[N];
 17 bool vis[N];
 18 
 19 #define mid (l+r>>1)
 20 #define L (o<<1)
 21 #define R (o<<1|1)
 22 void updata(int o,int l,int r,int pos,int v){
 23     if (l==r) t[o]=v;
 24     else{
 25         if (pos<=mid) updata(L,l,mid,pos,v);
 26         else updata(R,mid+1,r,pos,v);
 27         t[o]=t[L]^t[R];
 28     }
 29 }
 30 
 31 int ql,qr,ans=0;
 32 void query_it(int o,int l,int r){
 33     if (ql<=l && qr>=r) ans^=t[o];
 34     else{
 35         if (ql<=mid) query_it(L,l,mid);
 36         if (qr>mid) query_it(R,mid+1,r);
 37     }
 38 }
 39 //segment tree end
 40 
 41 void dfs(int x,int f,int deep){
 42     int y,maxsize=0;
 43     vis[x]=1; fa[x]=f; dep[x]=deep; size[x]=1; son[x]=0;
 44     rep(i,G[x].size()){
 45         y=G[x][i];
 46         if (vis[y]) continue;
 47         dfs(y,x,deep+1);
 48         size[x]+=size[y];
 49         if (size[y]>maxsize) maxsize=size[y],son[x]=y;
 50     }
 51 }
 52 
 53 void connect(int x,int f){
 54     tid[x]=++cnt;
 55     top[x]=f; vis[x]=1;
 56     if (son[x]) connect(son[x],f);
 57     rep(i,G[x].size()){
 58         int y=G[x][i];
 59         if (!vis[y]) connect(y,y);
 60     }
 61 }
 62 
 63 void query(int x,int y){
 64     while(top[x]!=top[y]){
 65         if (dep[top[x]]<dep[top[y]]) swap(x,y);
 66         ql=tid[top[x]]; qr=tid[x];
 67         query_it(1,1,n);
 68         x=fa[top[x]];
 69     }
 70     if (dep[x]>dep[y]) swap(x,y);
 71     ql=tid[x]; qr=tid[y];
 72     query_it(1,1,n);
 73 }
 74 
 75 int main(){
 76 //    freopen("file.in","r",stdin);
 77     scanf("%d",&n);
 78     F(i,1,n) scanf("%d",&a[i]);
 79     int x,y;
 80     F(i,2,n){
 81         scanf("%d%d",&x,&y);
 82         G[x].pb(y);
 83         G[y].pb(x);
 84     }
 85     dfs(1,0,1);
 86     memset(vis,0,sizeof vis);
 87     connect(1,1);
 88     F(i,1,n) updata(1,1,n,tid[i],a[i]);
 89     int q;
 90     scanf("%d",&q);
 91     char cmd[3];
 92     F(i,1,q){
 93         scanf("%s%d%d",cmd,&x,&y);
 94         if (cmd[0]==‘Q‘){
 95             ans=0;
 96             query(x,y);
 97             printf(ans ? "Yes\n" : "No\n");
 98         }
 99         else updata(1,1,n,tid[x],y);
100     }
101     return 0;
102 }