HDU 5274 (tree link partitioning)

HDU 5274 (tree link partitioning)

The first question of tree link splitting, QAQ.

 

 

#pragma comment(linker, "/STACK:102400000,102400000")#include 
 
  #include 
  
   #include 
   
    using namespace std;typedef long long ll;const ll mod = 1e9 + 7;const int maxn = 1e5 + 10;#define to first#define next second#define foreach(it,v) for(__typeof(v.begin()) it = v.begin(); it != v.end(); ++it)int pos[maxn],head[maxn],fa[maxn],son[maxn];int a[maxn],siz[maxn],root[maxn],dep[maxn];typedef pair
    
      Edge;Edge edges[maxn<<1];int e,tot;void AddEdge(int u,int v){    edges[++e] = make_pair(v,head[u]);head[u] = e;    edges[++e] = make_pair(u,head[v]);head[v] = e;}void pre(int u){    siz[u] = 1;son[u] = 0;    dep[u] = dep[fa[u]] + 1;    for(int i = head[u]; i ; i = edges[i].next) {        int v = edges[i].to;        if(v == fa[u])continue;        fa[v] = u;        pre(v);        siz[u] += siz[v];        if(siz[son[u]] < siz[v]) son[u] = v;    }}void built(int u,int t){    root[u] = t;    pos[u] = ++tot;    if(son[u] < 1) return;    built(son[u],t);    for(int i = head[u]; i ; i = edges[i].next) {        int v = edges[i].to;        if(v == fa[u] || v == son[u])continue;        built(v,v);    }}int seg[maxn<<2];int ql,qr,x,v;void Modify(int o,int L,int R){    if(L == R) {        seg[o] = v;        return ;    }    int mid = (L+R)>>1;    if(x<=mid) Modify(o<<1,L,mid);    else Modify(o<<1|1,mid+1,R);    seg[o] = seg[o<<1] ^ seg[o<<1|1];}int Queryseg(int o,int L,int R){    if(ql<=L&&qr>=R) return seg[o];    int mid = (L+R) >> 1;    int res = 0;    if(ql <= mid) res = Queryseg(o<<1,L,mid);    if(qr > mid) res ^= Queryseg(o<<1|1,mid+1,R);    return res;}int solve(int u,int v){    int res = 0;    while(root[u] != root[v]) {        if(dep[root[u]] < dep[root[v]]) swap(u,v);        ql = pos[root[u]],qr = pos[u];        res ^= Queryseg(1,1,tot);        u = fa[root[u]];    }    ql = pos[u],qr = pos[v];    if(ql > qr) swap(ql,qr);    res ^= Queryseg(1,1,tot);    return res;}int main(int argc, char const *argv[]){    int T;scanf("%d",&T);    while(T--) {        int N,Q;scanf("%d%d",&N,&Q);        dep[0] = e = tot = 0;        memset(seg,0,sizeof seg);        memset(head,0,sizeof(head[0])*(N+1));        for(int i = 1; i < N; i++) {            int u,v;scanf("%d%d",&u,&v);            AddEdge(u,v);        }        fa[1] = siz[0] = 0;        pre(1);        built(1,1);        for(int i = 1; i <= N; i++) {            scanf("%d",&v); ++v; x = pos[i];            Modify(1,1,tot);        }        while(Q--) {            int op;scanf("%d",&op);            if(op==0) {                scanf("%d%d",&x,&v);x = pos[x]; ++v;                Modify(1,1,tot);            } else {                scanf("%d%d",&ql,&qr);                int ans = solve(ql,qr);                printf("%d\n", ans - 1);            }        }    }    return 0;}