## COCI '11 Contest 1 #3 X3

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Points: 7 (partial)
Time limit: 1.0s
Memory limit: 32M

Problem types

Mirko has recently been visited by extraterrestrials from planet X3, where everyone's name is a positive integer. All residents of the planet know each other. Two X3-ians calculate the strength of their friendship by converting their names to binary, aligning them one under the other, and writing a digit in each column: if the two binary digits in that column are equal, if they differ. The binary result is then converted back to the decimal system.

For example, the friendship value of and equals :

The value of a planet in the Universe is defined as the sum of all friendship values. Mirko has asked you to help him compute the value of planet X3!

#### Input Specification

The first line of input contains the positive integer (the number of residents of planet X3, ).

The next lines contain the names of residents - positive integers smaller than , one per line.

#### Output Specification

The only line of output must contain the value of planet X3.

#### Sample Input 1

2
19
10

#### Sample Output 1

25

#### Sample Input 2

3
7
3
5

#### Sample Output 2

12

#### Explanation for Sample Output 2

The friendship value of residents and equals , for residents and it equals , and for residents and it equals . The solution is .

#### Sample Input 3

5
9
13
1
9
6

#### Sample Output 3

84