hdu3966(数链剖分+线段树区间更新）

来源：互联网发布：阿里云pc 编辑：程序博客网时间：2024/06/07 11:07

线段树区间更新得通过新映射的区间进行更新。

PS：当初ad数组开小了，wa了好好几次，可惜

#include<bits/stdc++.h>using namespace std;typedef long long ll;typedef pair<int,int> P;#define fi first#define se second#define INF 0x3f3f3f3f#define clr(x,y) memset(x,y,sizeof x)#define PI acos(-1.0)#define ITER set<int>::iteratorconst int Mod = 1e9 + 7;const int maxn = 5e4 + 10;struct Edge{    int to,next;}edge[maxn << 2];int head[maxn],edge_num,top[maxn],fa[maxn],son[maxn],id[maxn],deq[maxn],siz[maxn],num;ll tree[maxn<<2], a[maxn],ad[maxn << 2];void add(int x,int y){    edge[edge_num] = (Edge){y,head[x]};    head[x] = edge_num++;}//第一次搜索找出siz[],son[],deq[],fa[]void dfs1(int rt,int pa,int d){    deq[rt] = d;    son[rt] = 0;    fa[rt] = pa;    siz[rt] = 1;    for(int i=head[rt]; i!=-1; i=edge[i].next){        int t = edge[i].to;        if(t != fa[rt]){            dfs1(t,rt,d+1);            siz[rt] += siz[t];            if(siz[son[rt]] < siz[t]){//如果父节点的son[rt]的iz[]小于子节点的siz[]更新son[]                son[rt] = t;            }        }    }}//第二次搜索找到w[],top[]void dfs2(int rt,int tp){    top[rt] = tp;    id[rt] = ++num;    if(son[rt] != 0)        dfs2(son[rt],tp);//如果当前父节点纯在son 那么为了让链在线段树中连续 先对son[]进行搜索，并且重边顶端的点相同。    for(int i=head[rt]; i!=-1; i=edge[i].next){        int t = edge[i].to;        if(t != fa[rt] && son[rt] != t){            dfs2(t,t);        }    }}void update(int x,ll val,int l,int r,int rt){    if(l == r){tree[rt] = val;return ;}    int mid = (l + r) >> 1;    if(mid >= x)        update(x,val,l,mid,rt << 1);    else update(x,val,mid + 1,r,rt << 1 | 1);    tree[rt] = tree[rt << 1] + tree[rt << 1| 1];}ll query(int L,int R,int l,int r,int rt){    if(l == L && r == R)return tree[rt];    int mid = (l + r) >> 1;    if(ad[rt] != 0)    {        tree[rt << 1] += ad[rt] * (mid - l + 1);tree[rt << 1|1] += ad[rt] * (r - mid);        ad[rt << 1] += ad[rt];ad[rt << 1|1] += ad[rt];ad[rt] = 0;    }    ll ret = 0;    if(R <= mid)ret += query(L,R,l,mid,rt << 1);    else if(L >= mid + 1)ret += query(L,R,mid + 1,r,rt << 1 | 1 );    else        ret += query(L,mid,l,mid,rt << 1),ret += query(mid + 1,R,mid + 1,r,rt << 1|1);    return ret;}void update1(int L,int R,ll val,int l,int r,int rt){    if(L == l && R == r)    {        tree[rt] += 1ll * (R - L + 1) * val;        ad[rt] += val;return ;    }    int mid = (l + r) >> 1;    if(ad[rt] != 0)    {        tree[rt << 1] += ad[rt] * (mid - l + 1);tree[rt << 1|1] += ad[rt] * (r - mid);        ad[rt << 1] += ad[rt];ad[rt << 1|1] += ad[rt];ad[rt] = 0;    }    if(R <= mid)update1(L,R,val,l,mid,rt << 1);    else if(L >= mid + 1)update1(L,R,val,mid + 1,r,rt <<1|1);    else    {        update1(L,mid,val,l,mid,rt << 1);update1(mid+1,R,val,mid + 1,r,rt <<1|1);    }    tree[rt] = tree[rt << 1] + tree[rt << 1|1];}void updates(int u,int v,ll val){    int f1=top[u],f2=top[v];    while(f1!=f2){        if(deq[f1]<deq[f2]){            swap(f1,f2);            swap(u,v);        }        update1(id[f1],id[u],val,1,num,1);//        tmp+=query(id[f1],id[u],1,num,1);        u=fa[f1];f1=top[u];    }    if(deq[u]>deq[v]) swap(u,v);    update1(id[u],id[v],val,1,num,1);//    tmp+=query(id[u],id[v],1,num,1);//    return tmp;}ll solve(int u,int v){    int f1=top[u],f2=top[v];    ll tmp=0;    while(f1!=f2){        if(deq[f1]<deq[f2]){            swap(f1,f2);            swap(u,v);        }        tmp+=query(id[f1],id[u],1,num,1);        u=fa[f1];f1=top[u];    }    if(deq[u]>deq[v]) swap(u,v);    tmp+=query(id[u],id[v],1,num,1);    return tmp;}void Init(){    clr(head,-1);edge_num = 0;num = 0;clr(tree,0);clr(ad,0);}int main(){    int n,m,k;    while( ~ scanf("%d%d%d",&n,&m,&k))    {        Init();        for(int i = 1; i <= n;i ++)scanf("%lld",&a[i]);        while(m --){int x,y;scanf("%d%d",&x,&y);add(x,y);add(y,x);}        dfs1(1,1,1);dfs2(1,1);//        for(int i = 1; i <= n; i ++)cout << i << " <_> " << id[i] << endl;        for(int i = 1;i <= n; i ++)update(id[i],a[i],1,num,1);        while(k --)        {            char s[4];int x,y,z;scanf("%s",s);            if(s[0] == 'I' || s[0] == 'D')            {                scanf("%d%d%d",&x,&y,&z);                updates(x,y,s[0] == 'I' ? z : -z);            }            else            {                int x;scanf("%d",&x);                printf("%lld\n",solve(x,x));            }        }    }    return 0;}

附上树状数组代码：

#include<bits/stdc++.h>using namespace std;typedef long long ll;typedef pair<int,int> P;#define fi first#define se second#define INF 0x3f3f3f3f#define clr(x,y) memset(x,y,sizeof x)#define PI acos(-1.0)#define ITER set<int>::iteratorconst int Mod = 1e9 + 7;const int maxn = 5e4 + 10;struct Edge{    int to,next;}edge[maxn << 2];int head[maxn],edge_num,top[maxn],fa[maxn],son[maxn],id[maxn],deq[maxn],siz[maxn],num;ll tree[maxn], a[maxn];void add(int x,int y){    edge[edge_num] = (Edge){y,head[x]};    head[x] = edge_num++;}//第一次搜索找出siz[],son[],deq[],fa[]void dfs1(int rt,int pa,int d){    deq[rt] = d;    son[rt] = 0;    fa[rt] = pa;    siz[rt] = 1;    for(int i=head[rt]; i!=-1; i=edge[i].next){        int t = edge[i].to;        if(t != fa[rt]){            dfs1(t,rt,d+1);            siz[rt] += siz[t];            if(siz[son[rt]] < siz[t]){//如果父节点的son[rt]的iz[]小于子节点的siz[]更新son[]                son[rt] = t;            }        }    }}//第二次搜索找到w[],top[]void dfs2(int rt,int tp){    top[rt] = tp;    id[rt] = ++num;    if(son[rt] != 0)        dfs2(son[rt],tp);//如果当前父节点纯在son 那么为了让链在线段树中连续 先对son[]进行搜索，并且重边顶端的点相同。    for(int i=head[rt]; i!=-1; i=edge[i].next){        int t = edge[i].to;        if(t != fa[rt] && son[rt] != t){            dfs2(t,t);        }    }}inline int lowbit(int x){return x & (-x);}ll get(int x){    ll ret = 0;    for(int i = x; i > 0;i -= lowbit(i))ret += tree[i];    return ret;}void update(int x,ll val){    for(int i = x; i < maxn; i += lowbit(i))tree[i] += val;}void update1(int l,int r,ll val){    update(l,val);update(r + 1,-val);}void updates(int u,int v,ll val){    int f1=top[u],f2=top[v];    while(f1!=f2){        if(deq[f1]<deq[f2]){            swap(f1,f2);            swap(u,v);        }        update1(id[f1],id[u],val);//        tmp+=query(id[f1],id[u],1,num,1);        u=fa[f1];f1=top[u];    }    if(deq[u]>deq[v]) swap(u,v);    update1(id[u],id[v],val);//    tmp+=query(id[u],id[v],1,num,1);//    return tmp;}void Init(){    clr(head,-1);edge_num = 0;num = 0;clr(tree,0);}int main(){    int n,m,k;    while( ~ scanf("%d%d%d",&n,&m,&k))    {        Init();        for(int i = 1; i <= n;i ++)scanf("%lld",&a[i]);        while(m --){int x,y;scanf("%d%d",&x,&y);add(x,y);add(y,x);}        dfs1(1,1,1);dfs2(1,1);//        for(int i = 1; i <= n; i ++)cout << i << " <-> " << id[i] << endl;        for(int i = 1;i <= n; i ++)update(id[i],a[i]),update(id[i] + 1,-a[i]);        while(k --)        {            char s[4];int x,y,z;scanf("%s",s);            if(s[0] == 'I' || s[0] == 'D')            {                scanf("%d%d%d",&x,&y,&z);                updates(x,y,s[0] == 'I' ? z : -z);            }            else            {                int x;scanf("%d",&x);                printf("%lld\n",get(id[x]) );            }        }    }    return 0;}

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