BZOJ 3531 旅行【树链剖分】

青旅半醒 2022-08-09 01:51 140阅读 0赞

[\[Sdoi2014\]][Sdoi2014]  
简单的树链剖分  
以每个信仰应该建一个线段树，空间复杂度为*O*(5×1010)  
因此会爆空间，所以需要动态申请空间。

// whn6325689
    // Mr.Phoebe
    // http://blog.csdn.net/u013007900
    #include <algorithm>
    #include <iostream>
    #include <iomanip>
    #include <cstring>
    #include <climits>
    #include <complex>
    #include <fstream>
    #include <cassert>
    #include <cstdio>
    #include <bitset>
    #include <vector>
    #include <deque>
    #include <queue>
    #include <stack>
    #include <ctime>
    #include <set>
    #include <map>
    #include <cmath>
    #include <functional>
    #include <numeric>
    #pragma comment(linker, "/STACK:1024000000,1024000000")
    
    
    using namespace std;
    
    #define eps 1e-9
    #define PI acos(-1.0)
    #define INF 0x3f3f3f3f
    #define LLINF 1LL<<62
    #define speed std::ios::sync_with_stdio(false);
    
    typedef long long ll;
    typedef unsigned long long ull;
    typedef long double ld;
    typedef pair<ll, ll> pll;
    typedef complex<ld> point;
    typedef pair<int, int> pii;
    typedef pair<pii, int> piii;
    typedef vector<int> vi;
    
    #define CLR(x,y) memset(x,y,sizeof(x))
    #define CPY(x,y) memcpy(x,y,sizeof(x))
    #define clr(a,x,sz) memset(a,x,sizeof(a[0])*(sz))
    #define cpy(a,x,sz) memcpy(a,x,sizeof(a[0])*(sz))
    #define debug(a) cout << #a" = " << (a) << endl;
    #define debugarry(a, n) for (int i = 0; i < (n); i++) { cout << #a"[" << i << "] = " << (a)[i] << endl; }
    
    #define mp(x,y) make_pair(x,y)
    #define pb(x) push_back(x)
    #define lowbit(x) (x&(-x))
    
    #define MID(x,y) (x+((y-x)>>1))
    #define getidx(l,r) (l+r | l!=r)
    #define ls getidx(l,mid)
    #define rs getidx(mid+1,r)
    #define lson l,mid
    #define rson mid+1,r
    
    template<class T>
    inline bool read(T &n)
    {
        T x = 0, tmp = 1;
        char c = getchar();
        while((c < '0' || c > '9') && c != '-' && c != EOF) c = getchar();
        if(c == EOF) return false;
        if(c == '-') c = getchar(), tmp = -1;
        while(c >= '0' && c <= '9') x *= 10, x += (c - '0'),c = getchar();
        n = x*tmp;
        return true;
    }
    template <class T>
    inline void write(T n)
    {
        if(n < 0)
        {
            putchar('-');
            n = -n;
        }
        int len = 0,data[20];
        while(n)
        {
            data[len++] = n%10;
            n /= 10;
        }
        if(!len) data[len++] = 0;
        while(len--) putchar(data[len]+48);
    }
    //-----------------------------------
    
    const int MAXN=100010;
    
    struct SegTree *nil;
    
    struct SegTree
    {
        SegTree *son[2];
        int maxn,sum;
    
        SegTree()
        {
            maxn=sum=0;
            son[0]=son[1]=nil;
        }
    
        void update(int l,int r,int x,int c)
        {
            if(l==r)
            {
                maxn=sum=c;
                return;
            }
            int mid=MID(l,r);
            if(x<=mid)
            {
                if(son[0]==nil)
                    son[0]=new SegTree();
                son[0]->update(lson,x,c);
            }
            else
            {
                if(son[1]==nil)
                    son[1]=new SegTree();
                son[1]->update(rson,x,c);
            }
            maxn=max(son[0]->maxn,son[1]->maxn);
            sum=son[0]->sum+son[1]->sum;
        }
        int GetSum(int l,int r,int x,int y)
        {
            if(this==nil) return 0;
            if(l==x && y==r)    return sum;
            int mid=MID(l,r);
            if(y <= mid) return son[0]->GetSum(lson,x,y);
            if(x > mid)      return son[1]->GetSum(rson,x,y);
            int left=son[0]->GetSum(lson,x,mid);
            int right=son[1]->GetSum(rson,mid+1,y);
            return left + right;
        }
        int GetMax(int l,int r,int x,int y)
        {
            if(this==nil) return 0;
            if(l==x && y==r)    return maxn;
            int mid=MID(l,r);
            if(y <= mid) return son[0]->GetMax(lson,x,y);
            if(x > mid)      return son[1]->GetMax(rson,x,y);
            int left=son[0]->GetMax(lson,x,mid);
            int right=son[1]->GetMax(rson,mid+1,y);
            return max(left,right);
        }
    } none,*root[MAXN];
    
    int n,m;
    struct Edge
    {
        int to,next;
    } e[MAXN<<1];
    int head[MAXN],tot;
    
    void init()
    {
        CLR(head,-1);
        tot=0;nil=&none;
    }
    
    inline void addedge(int x,int y)
    {
        e[tot].next=head[x];
        e[tot].to=y;
        head[x]=tot++;
    }
    
    int p[MAXN],belief[MAXN];
    char str[22];
    int sz[MAXN],son[MAXN],fa[MAXN],dep[MAXN];
    int top[MAXN],dfn[MAXN],cnt;
    
    void dfs(int x,int last)
    {
        dep[x]=dep[last]+1;
        fa[x]=last;
        son[x]=-1;
        sz[x]=1;
        int max_sz=0;
        for(int i=head[x]; ~i; i=e[i].next)
        {
            if(e[i].to==last)  continue;
            dfs(e[i].to,x);
            sz[x]+=sz[e[i].to];
            if(sz[e[i].to]>max_sz)
                max_sz=sz[e[i].to],son[x]=e[i].to;
        }
    }
    
    void getid(int x,int _top)
    {
        dfn[x]=++cnt;
        top[x]=_top;
        if(~son[x])  getid(son[x],_top);
        for(int i=head[x]; ~i; i=e[i].next)
        {
            if(e[i].to==fa[x] || e[i].to==son[x])  continue;
            getid(e[i].to,e[i].to);
        }
    }
    
    
    inline int GetSum(int x,int y,int p)
    {
        int re=0;
        while(top[x]!=top[y])
        {
            if(dep[top[x]] < dep[top[y]])  swap(x,y);
            re+=root[p]->GetSum(1,n,dfn[top[x]],dfn[x]);
            x=fa[top[x]];
        }
        if(dep[x]<dep[y])    swap(x,y);
        re += root[p]->GetSum(1,n,dfn[y],dfn[x]);
        return re;
    }
    
    inline int GetMax(int x,int y,int p)
    {
        int re=0;
        while(top[x] != top[y])
        {
            if(dep[top[x]] < dep[top[y]])  swap(x,y);
            re=max(re,root[p]->GetMax(1,n,dfn[top[x]],dfn[x]));
            x=fa[top[x]];
        }
        if(dep[x]<dep[y])    swap(x,y);
        re=max(re,root[p]->GetMax(1,n,dfn[y],dfn[x]));
        return re;
    }
    
    int main()
    {
        init();
        scanf("%d %d",&n,&m);
        for(int i=0; i<MAXN; i++)
            root[i]=new SegTree();
        for(int i=1; i<=n; i++)
            scanf("%d %d",&p[i],&belief[i]);
        for(int x,y,i=1; i<n; i++)
        {
            scanf("%d %d",&x,&y);
            addedge(x,y),addedge(y,x);
        }
        dfs(1,0);
        getid(1,1);
        for(int i=1; i<=n; i++)
            root[belief[i]]->update(1,n,dfn[i],p[i]);
        for(int x,y,i=1; i<=m; i++)
        {
            scanf("%s%d%d",str,&x,&y);
            if(str[0]=='C' && str[1]=='C')
            {
                root[belief[x]]->update(1,n,dfn[x],0);
                root[belief[x]=y]->update(1,n,dfn[x],p[x]);
            }
            else if(str[0]=='C' && str[1]=='W')
                root[belief[x]]->update(1,n,dfn[x],p[x]=y);
            else if(str[0]=='Q' && str[1]=='S')
                printf("%d\n",GetSum(x,y,belief[x]));
            else
                printf("%d\n",GetMax(x,y,belief[x]));
        }
        return 0;
    }

[Sdoi2014]: http://www.lydsy.com/JudgeOnline/problem.php?id=3531