1064. Complete Binary Search Tree

두 갈래 정렬 트 리:
http://www.patest.cn/contests/pat-a-practise/1064  

  1 #include <stdio.h>

  2  

  3 #include <math.h>

  4  

  5 #include <algorithm>

  6  

  7 using namespace std;

  8  

  9 struct Node

 10  

 11 {

 12  

 13    Node* lchild;

 14  

 15    Node* rchild;

 16  

 17    int val;

 18  

 19 }Tree[1001];

 20  

 21  

 22  

 23 int loc;

 24  

 25 Node * create()

 26  

 27 {

 28  

 29 Tree[loc].lchild=NULL;

 30  

 31 Tree[loc].rchild=NULL;

 32  

 33 return &Tree[loc++];

 34  

 35 }

 36  

 37 bool cmp(int a,int b)

 38  

 39 {

 40  

 41    return a<b;

 42  

 43 }

 44  

 45 Node* fun(int ans[],int len,Node* T)

 46  

 47 {

 48  

 49       int com;//                  

 50  

 51  int left;//   T         

 52  

 53  int right;// ———— ———————

 54  

 55  int LastLevel;//         

 56  

 57  int LeftLastLevel;//            

 58  

 59  int level;//  

 60  

 61  //   level

 62  

 63  level=0;

 64  

 65   while(pow(2.0,level)-1<len)//           2^(level)-1

 66  

 67      ++level;

 68  

 69   LastLevel=len-pow(2.0,level-1)+1;

 70  

 71   if(LastLevel<pow(2.0,level-1)/2)// n         2^(n-1)

 72  

 73   LeftLastLevel=LastLevel; //

 74  

 75   else LeftLastLevel=pow(2.0,level-1)/2;

 76  

 77   left=(pow(2.0,level-1)-1-1)/2+LeftLastLevel;

 78  

 79   right=len-left-1;

 80  

 81    T=create();

 82  

 83    T->val=ans[left+1];

 84  

 85 if(left>0)

 86  

 87    T->lchild=fun(ans,left,T->lchild);

 88  

 89 if(right>0)

 90  

 91    T->rchild=fun(ans+left+1,right,T->rchild);    

 92  

 93   return T;

 94  

 95 }

 96  

 97 int main()

 98  

 99 {

100  

101      int n,i;

102  

103 while(scanf("%d",&n)!=EOF)

104  

105 {

106  

107 getchar();

108  

109    int ans[1001];

110  

111    for(i=1;i<=n;i++)

112  

113   scanf("%d",&ans[i]);

114  

115 getchar();

116  

117 sort(ans+1,ans+1+n,cmp);

118  

119 Node* T=NULL;

120  

121 loc=0;

122  

123 T=fun(ans,n,T);

124  

125 //    

126  

127 Node* que[1001];

128  

129 int rear=0,front=0;

130  

131 que[rear++]=T;

132  

133 printf("%d",T->val);

134  

135 while(rear!=front)

136  

137 {

138  

139 Node* temp=que[front++];

140  

141  

142  

143 if(temp->rchild!=NULL)

144  

145 {

146  

147  que[rear++]=temp->lchild;

148  

149  que[rear++]=temp->rchild;

150  

151  printf(" %d %d",temp->lchild->val,temp->rchild->val);

152  

153 }

154  

155 else if(temp->lchild!=NULL)

156  

157 {

158  

159               que[rear++]=temp->lchild;

160  

161  printf(" %d",temp->lchild->val);

162  

163 }

164  

165 }

166  

167 printf("
");

168  

169 }

170  

171   return 0;

172  

173 }