On a plane are
n points (
xi,
yi) with integer coordinates between
0 and
106. The distance between the two points with numbers
a and
b is said to be the following value:
(the distance calculated by such formula is called
Manhattan distance).
We call a hamiltonian path to be some permutation
pi of numbers from
1 to
n. We say that the length of this path is value
.
Find some hamiltonian path with a length of no more than
25×108. Note that you do not have to minimize the path length.
Output
Print the permutation of numbers
pi from
1 to
n − the sought Hamiltonian path. The permutation must meet the inequality
.
If there are multiple possible answers, print any of them.
It is guaranteed that the answer exists.
Note
In the sample test the total distance is:
(|5-3|+|0-4|)+(|3-0|+|4-7|)+(|0-8|+|7-10|)+(|8-9|+|10-12|)=2+4+3+3+8+3+1+2=26