Adjacent Replacements
Contest: Codeforces Round 498 (Div. 3)
Difficulty rating: 800
Tags: implementation

Mishka got an integer array $$$a$$$ of length $$$n$$$ as a birthday present (what a surprise!).

Mishka doesn't like this present and wants to change it somehow. He has invented an algorithm and called it "Mishka's Adjacent Replacements Algorithm". This algorithm can be represented as a sequence of steps:

- Replace each occurrence of $$$1$$$ in the array $$$a$$$ with $$$2$$$;
- Replace each occurrence of $$$2$$$ in the array $$$a$$$ with $$$1$$$;
- Replace each occurrence of $$$3$$$ in the array $$$a$$$ with $$$4$$$;
- Replace each occurrence of $$$4$$$ in the array $$$a$$$ with $$$3$$$;
- Replace each occurrence of $$$5$$$ in the array $$$a$$$ with $$$6$$$;
- Replace each occurrence of $$$6$$$ in the array $$$a$$$ with $$$5$$$;
- $$$\dots$$$
- Replace each occurrence of $$$10^9 - 1$$$ in the array $$$a$$$ with $$$10^9$$$;
- Replace each occurrence of $$$10^9$$$ in the array $$$a$$$ with $$$10^9 - 1$$$.

Note that the dots in the middle of this algorithm mean that Mishka applies these replacements for each pair of adjacent integers ($$$2i - 1, 2i$$$) for each $$$i \in\{1, 2, \ldots, 5 \cdot 10^8\}$$$ as described above.

For example, for the array $$$a = [1, 2, 4, 5, 10]$$$, the following sequence of arrays represents the algorithm:

$$$[1, 2, 4, 5, 10]$$$ $$$\rightarrow$$$ (replace all occurrences of $$$1$$$ with $$$2$$$) $$$\rightarrow$$$ $$$[2, 2, 4, 5, 10]$$$ $$$\rightarrow$$$ (replace all occurrences of $$$2$$$ with $$$1$$$) $$$\rightarrow$$$ $$$[1, 1, 4, 5, 10]$$$ $$$\rightarrow$$$ (replace all occurrences of $$$3$$$ with $$$4$$$) $$$\rightarrow$$$ $$$[1, 1, 4, 5, 10]$$$ $$$\rightarrow$$$ (replace all occurrences of $$$4$$$ with $$$3$$$) $$$\rightarrow$$$ $$$[1, 1, 3, 5, 10]$$$ $$$\rightarrow$$$ (replace all occurrences of $$$5$$$ with $$$6$$$) $$$\rightarrow$$$ $$$[1, 1, 3, 6, 10]$$$ $$$\rightarrow$$$ (replace all occurrences of $$$6$$$ with $$$5$$$) $$$\rightarrow$$$ $$$[1, 1, 3, 5, 10]$$$ $$$\rightarrow$$$ $$$\dots$$$ $$$\rightarrow$$$ $$$[1, 1, 3, 5, 10]$$$ $$$\rightarrow$$$ (replace all occurrences of $$$10$$$ with $$$9$$$) $$$\rightarrow$$$ $$$[1, 1, 3, 5, 9]$$$. The later steps of the algorithm do not change the array.

Mishka is very lazy and he doesn't want to apply these changes by himself. But he is very interested in their result. Help him find it.

Input format:
The first line of the input contains one integer number $$$n$$$ ($$$1 \le n \le 1000$$$) — the number of elements in Mishka's birthday present (surprisingly, an array).

The second line of the input contains $$$n$$$ integers $$$a_1, a_2, \dots, a_n$$$ ($$$1 \le a_i \le 10^9$$$) — the elements of the array.

Output format:
Print $$$n$$$ integers — $$$b_1, b_2, \dots, b_n$$$, where $$$b_i$$$ is the final value of the $$$i$$$-th element of the array after applying "Mishka's Adjacent Replacements Algorithm" to the array $$$a$$$. Note that you cannot change the order of elements in the array.

Constraints:
Time limit: 1.0 s
Memory limit: 256.0 MB

Note:
The first example is described in the problem statement.

Example input:
5
1 2 4 5 10

Example output:
1 1 3 5 9

Example input:
10
10000 10 50605065 1 5 89 5 999999999 60506056 1000000000

Example output:
9999 9 50605065 1 5 89 5 999999999 60506055 999999999

Editorial:
It is easy to see that for the odd elements there is no changes after applying the algorithm described in the problem statement, and for the even elements there is only one change: each of the even elements will be decreased by $$$1$$$. So we can iterate over all the elements of the array and print $$$a_i - (a_i \% 2)$$$, where $$$x \% y$$$ is taking $$$x$$$ modulo $$$y$$$.
Overall complexity is $$$O(n)$$$.