题目链接:http://acm.fzu.edu.cn/problem.php?pid=2277
Problem Description
There is a rooted tree with n nodes, number from 1-n. Root’s number is 1.Each node has a value ai.
Initially all the node’s value is 0.
We have q operations. There are two kinds of operations.
1 v x k : a[v]+=x , a[v’]+=x-k (v’ is child of v) , a[v’’]+=x-2*k (v’’ is child of v’) and so on.
2 v : Output a[v] mod 1000000007(10^9 + 7).
Input
First line contains an integer T (1 ≤ T ≤ 3), represents there are T test cases.
In each test case:
The first line contains a number n.
The second line contains n-1 number, p2,p3,…,pn . pi is the father of i.
The third line contains a number q.
Next q lines, each line contains an operation. (“1 v x k” or “2 v”)
1 ≤ n ≤ 3*10^5
1 ≤ pi < i
1 ≤ q ≤ 3*10^5
1 ≤ v ≤ n; 0 ≤ x < 10^9 + 7; 0 ≤ k < 10^9 + 7
Output
For each operation 2, outputs the answer.
Sample Input
Sample Output
Source
第八届福建省大学生程序设计竞赛-重现赛(感谢承办方厦门理工学院)
题意:略
题目分析:略
1 #include<cstdio> 2 #include<iostream> 3 #include<cstring> 4 #include<algorithm> 5 #include<vector> 6 #define Pii pair<int,int> 7 #define fi first 8 #define se second 9 #define mp make_pair 10 #define pb push_back 11 #define maxn 300100 12 #define LL long long 13 #define lson l,m,rt<<1 14 #define rson m+1,r,rt<<1|1 15 #define Mod 1000000007 16 using namespace std; 17 vector<int> G[maxn]; 18 int n,k,x,ti=0; 19 LL tot[maxn]; 20 LL C[maxn],add[maxn],Add[maxn*4]; 21 int l[maxn],r[maxn]; 22 LL deep[maxn]; 23 inline int lowbit(int x){return (x&-x);} 24 inline void update(int x,LL y,LL t){ 25 while(x<=n){ 26 C[x]+=y; 27 tot[x]+=t; 28 x+=lowbit(x); 29 } 30 } 31 LL query(int x){ 32 LL ans=0; 33 while (x>0){ 34 ans+=C[x]; 35 x-=lowbit(x); 36 } 37 return ans; 38 } 39 LL Query(int x){ 40 LL ans=0; 41 while (x>0){ 42 ans+=tot[x]; 43 x-=lowbit(x); 44 } 45 return ans; 46 } 47 void dfs(int x,int fa,int dep){ 48 l[x]=++ti; 49 deep[l[x]]=dep; 50 for(int i=0;i<G[x].size();i++){ 51 if(G[x][i]==fa) continue; 52 dfs(G[x][i],x,dep+1); 53 } 54 r[x]=ti; 55 } 56 int main(){ 57 int u,Q,v,T,opt; 58 cin>>T; 59 while(T--){ 60 cin>>n; 61 memset(C,0,sizeof(C)); 62 memset(tot,0,sizeof(tot)); 63 for(int i=2;i<=n;i++){ 64 scanf("%d",&u); 65 G[u].pb(i); 66 } 67 ti=0; 68 dfs(1,-1,1); 69 LL res; 70 cin>>Q; 71 for(int i=1;i<=Q;i++){ 72 scanf("%d",&opt); 73 if(opt==1){ 74 scanf("%d%d%d",&v,&x,&k); 75 update(l[v],x+(LL)k*deep[l[v]],k); 76 update(r[v]+1,-x-(LL)k*deep[l[v]],-k); 77 } 78 else{ 79 scanf("%d",&v); 80 res=query(l[v])-Query(l[v])*deep[l[v]]; 81 while(res<0) res+=Mod; 82 res%=Mod; 83 printf("%I64d\n",res); 84 } 85 } 86 for(int i=1;i<=n;i++) G[i].clear(); 87 } 88 return 0; 89 }