[2016-02-08][UVA][122][Trees on the level]
| Time Limit: 3000MS | Memory Limit: Unknown | 64bit IO Format: %lld & %llu |
Description
Background
Trees are fundamental in many branches of computer science. Current state-of-the art parallel computers such as Thinking Machines' CM-5 are based on fat trees. Quad- and octal-trees are fundamental to many algorithms in computer graphics.
This problem involves building and traversing binary trees.
The Problem
Given a sequence of binary trees, you are to write a program that prints a level-order traversal of each tree. In this problem each node of a binary tree contains a positive integer and all binary trees have have fewer than 256 nodes.
In a level-order traversal of a tree, the data in all nodes at a given level are printed in left-to-right order and all nodes at level k are printed before all nodes at level k+1.
For example, a level order traversal of the tree
is: 5, 4, 8, 11, 13, 4, 7, 2, 1.
In this problem a binary tree is specified by a sequence of pairs (n,s) where n is the value at the node whose path from the root is given by the string s. A path is given be a sequence of L's andR's where L indicates a left branch and R indicates a right branch. In the tree diagrammed above, the node containing 13 is specified by (13,RL), and the node containing 2 is specified by (2,LLR). The root node is specified by (5,) where the empty string indicates the path from the root to itself. A binary tree is considered to be completely specified if every node on all root-to-node paths in the tree is given a value exactly once.
The Input
The input is a sequence of binary trees specified as described above. Each tree in a sequence consists of several pairs (n,s) as described above separated by whitespace. The last entry in each tree is (). No whitespace appears between left and right parentheses.
All nodes contain a positive integer. Every tree in the input will consist of at least one node and no more than 256 nodes. Input is terminated by end-of-file.
The Output
For each completely specified binary tree in the input file, the level order traversal of that tree should be printed. If a tree is not completely specified, i.e., some node in the tree is NOT given a value or a node is given a value more than once, then the string ``not complete'' should be printed.
Sample Input
(11,LL) (7,LLL) (8,R) (5,) (4,L) (13,RL) (2,LLR) (1,RRR) (4,RR) () (3,L) (4,R) ()
Sample Output
5 4 8 11 13 4 7 2 1 not complete
- 时间:2016-02-07 23:22:52 星期日
- 题目编号:UVA 122
- 题目大意:输入一棵树,BFS输出结果
- 方法:
- 有 ',' 表示 有数据,没有 ',' 表示结束输入
- 根据LLRR这个数据建树
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#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
using
namespace
std;
typedef
long
long
LL;
#define CLR(x,y) memset((x),(y),sizeof((x)))
#define FOR(x,y,z) for(int (x)=(y);(x)<(z);(x)++)
#define FORD(x,y,z) for(int (x)=(y);(x)>=(z);(x)--)
#define FOR2(x,y,z) for((x)=(y);(x)<(z);(x)++)
#define FORD2(x,y,z) for((x)=(y);(x)>=(z);(x)--)
const
int
maxn = 256 + 100;
char
str[maxn],son[maxn];
int
value,error;
struct
node{
int
v,have_value;
node *lson,*rson;
node():have_value(0),lson(NULL),rson(NULL){}
};
void
addnode(node *head,
int
v,
char
s[]){
if
(error)
return
;
char
*p = s;
if
(*p ==
')'
){
head->have_value = 1;
head->v = v;
return
;
}
while
(*p){
if
(*p ==
'L'
){
if
(!head->lson) head->lson =
new
node;
head = head->lson;
}
else
if
( *p ==
'R'
){
if
(!head->rson) head->rson =
new
node;
head = head->rson;
}
else
{
if
(head->have_value){
error = 1;
return
;
}
head->have_value = 1;
head->v = v;
}
p++;
}
}
int
res[maxn];
void
bfs(node *head){
if
(error){
puts
(
"not complete"
);
return
;
}
queue<node*> q;
q.push(head);
int
cnt = 0;
while
(!q.empty()){
node * cur = q.front();q.pop();
if
(!cur->have_value){
puts
(
"not complete"
);
return
;
}
res[cnt++] = cur->v;
if
(cur->lson) q.push(cur->lson);
if
(cur->rson) q.push(cur->rson);
}
FOR(i,0,cnt - 1)
printf
(
"%d "
,res[i]);
printf
(
"%d\n"
,res[cnt - 1]);
}
void
deltree(node * head){
if
(head){
if
(head->lson) deltree(head->lson);
if
(head->rson) deltree(head->rson);
delete
head;
}
}
int
main(){
node * root =
new
node;
error = 0;
while
(~
scanf
(
"%s"
,str)){
if
(!
strcmp
(str,
"()"
)){
bfs(root);
deltree(root);
error = 0;
root =
new
node;
continue
;
}
sscanf
(str,
"(%d,%s"
,&value,son);
addnode(root,value,son);
}
return
0;
}
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