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1105-S-Trees

題目大意:

給一棵完整的樹:

給出每一層的節點号(xi,同一層的節點共用一個号,從第一層到第n層不一定是從x1到xn,是打亂的)

給出所有葉子節點的值(如n=3,葉子節點有8個)

給出路徑v1v2v3...Vn:0走左子樹,1走右子樹,但是路徑是嚴格配置設定給x1x2x3...xn的,即如果第一層節點即根節點不是x1而是x3,走的第一步要根據路徑的v3來确定左子樹還是右子樹

輸出最後到達的葉子節點的值

思想:

到達每一個葉子節點的路徑是唯一的

s=s*2+(vvn[i][j]-'0');

資料結構的知識

父節點是i,左孩子是i*2,右孩子是2*i+1;

在這題中隻存儲葉子節點即可

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S-Trees

Time Limit: 1000MS

Memory Limit: 10000K

Total Submissions: 1439

Accepted: 773

Description

A Strange Tree  (S-tree) over the variable set Xn = {x1,x2,...,xn} is a binary tree  representing a Boolean function f:{0,1}->{0,1}. Each path of the S-tree  begins at the root node and consists of n+1 nodes. Each of the S-tree's nodes  has a depth, which is the amount of nodes between itself and the root (so the  root has depth 0). The nodes with depth less than n are called non-terminal  nodes. All non-terminal nodes have two children: the right child and the left  child. Each non-terminal node is marked with some variable xi from the  variable set Xn. All non-terminal nodes with the same depth are marked with  the same variable, and non-terminal nodes with different depth are marked  with different variables. So, there is a unique variable xi1 corresponding to  the root, a unique variable xi2 corresponding to the nodes with depth 1, and  so on. The sequence of the variables xi1,xi2,...,xin is called the variable  ordering. The nodes having depth n are called terminal nodes. They have no  children and are marked with either 0 or 1. Note that the variable ordering  and the distribution of 0's and 1's on terminal nodes are sufficient to  completely describe an S-tree. 

 As stated earlier, each S-tree represents a Boolean function f. If you have  an S-tree and values for the variables x1,x2,...,xn, then it is quite simple  to find out what f(x1,x2,...,xn) is: start with the root. Now repeat the  following: if the node you are at is labelled with a variable xi, then  depending on whether the value of the variable is 1 or 0, you go its right or  left child, respectively. Once you reach a terminal node, its label gives the  value of the function. 

Figure 1: S-trees  for the x1 and (x2 or x3) function

 On the picture, two S-trees representing the same Boolean  function,f(x1,x2,x3) = x1 and (x2 or x3), are shown. For the left tree, the  variable ordering is x1, x2, x3, and for the right tree it is x3, x1,  x2. 

 The values of the variables x1,x2,...,xn, are given as a Variable Values  Assignment (VVA) 

(x1 = b1, x2 = b2,  ..., xn = bn)

 with b1,b2,...,bn in {0,1}. For instance, ( x1 = 1, x2 = 1 x3 = 0) would be a  valid VVA for n = 3, resulting for the sample function above in the value  f(1,1,0) = 1 and (1 or 0) = 1. The corresponding paths are shown bold in the  picture. 

 Your task is to write a program which takes an S-tree and some VVAs and  computes f(x1,x2,...,xn) as described above.

Input

The input contains  the description of several S-trees with associated VVAs which you have to  process. Each description begins with a line containing a single integer n, 1  <= n <= 7, the depth of the S-tree. This is followed by a line describing  the variable ordering of the S-tree. The format of that line is xi1 xi2  ...xin. (There will be exactly n different space-separated strings). So, for  n = 3 and the variable ordering x3, x1, x2, this line would look as  follows: 

 x3 x1 x2 

 In the next line the distribution of 0's and 1's over the terminal nodes is  given. There will be exactly 2^n characters (each of which can be 0 or 1),  followed by the new-line character. The characters are given in the order in  which they appear in the S-tree, the first character corresponds to the  leftmost terminal node of the S-tree, the last one to its rightmost terminal  node. 

 The next line contains a single integer m, the number of VVAs, followed by m  lines describing them. Each of the m lines contains exactly n characters  (each of which can be 0 or 1), followed by a new-line character. Regardless  of the variable ordering of the S-tree, the first character always describes  the value of x1, the second character describes the value of x2, and so on.  So, the line 

 110 

 corresponds to the VVA ( x1 = 1, x2 = 1, x3 = 0). 

 The input is terminated by a test case starting with n = 0. This test case  should not be processed.

Output

For each S-tree,  output the line "S-Tree #j:", where j is the number of the S-tree.  Then print a line that contains the value of f(x1,x2,...,xn) for each of the  given m VVAs, where f is the function defined by the S-tree. 

 Output a blank line after each test case.

Sample  Input

3

x1 x2 x3

00000111

4

000

010

110

x3 x1 x2

00010011

Sample  Output

S-Tree #1:

0011

S-Tree #2:

Source

Mid-Central European  Regional Contest 1999

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 代碼:

# include <iostream>

# include <cstdio>

# include <string>

# include <cmath>

using namespace std;

int main()

{

int n,nvvn,i,j,s,m=0;

char ord[30],tnod[300];

cin>>n;

while(n!=0)

m++;

int* order=new int[n];

getchar();

gets(ord);

for(i=0;i<n;i++)

order[i]=(ord[1+i*3]-'0')-1;

}

cin>>tnod;

cin>>nvvn;

char (*vvn)[10]=new char[nvvn][10];

for(i=0;i<nvvn;i++)

cin>>vvn[i];

cout<<"S-Tree #"<<m<<":"<<endl;

for(j=0,s=0;j<n;j++)

cout<<tnod[s];

cout<<endl;

return 0;