2009_10-5_Practice1 E

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Special Container

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)

Design a container, which has two kinds of operation, push and pop.

Push: You should push the given number into the container.

Pop: Please find the middle number of the container. If these is n numbers in container, it will be the (n+1)/2-th num when sort increased. Then pop the number.

Input

The input contains one or more data sets. At first line of each input data set is an integer N (1<= N <= 100000) indicate the number of operations.

Then N lines follows, each line contains a number (0 or 1). "0" means a push operation, it's followed by an integer E. "1" means a pop operation.

You may assume all the numbers in the input file will be in the range of 32-bit integer.

Output

For each pop operation, you should print the integer popped. Please print "No Element!", if there is no number to pop. Please print a blank line after each data set.

 

Sample Input

9

0 10

0 -10

0 5

1

1

0 2

1

1

1

3

0 2

0 1

1

 

Sample Output

5

-10

2

10

No Element!

 

1

 

 

1.用樹狀數組的方法,因爲只有N次操作,但是不知道操作數範圍,所以要先離散化一下,那麼就要先記錄;

2.有兩種操作:push pop 在pop的時候怎樣找到位置在(n+1)/2的數呢。。。肯定不能排序 位置在那個地方的數的特點是前面存在一定數量比他小的,因爲是實時的操作,那麼用樹狀數組記錄某個

 

後記:我覺得這道題很強大。

首先剛開始看的時候我沒有想到,後來聽某牛說用樹狀數組可以解,就試着想了下

 

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