hdu3966(数链剖分+线段树区间更新）
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
using namespace std;
typedef long long ll;
typedef pair 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::iterator
const 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[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[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
using namespace std;
typedef long long ll;
typedef pair 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::iterator
const 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[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;
}