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CF1413A.Finding Sasuke
Finding Sasuke
Naruto has sneaked into the Orochimaru's lair and is now looking for Sasuke. There are rooms there. Every room has a door into it, each door can be described by the number of seals on it and their integer energies , , ..., . All energies are nonzero and do not exceed by absolute value. Also, is even.
In order to open a door, Naruto must find such seals with integer energies , , ..., that the following equality holds: $a_{1} \cdot b_{1} + a_{2} \cdot b_{2} + ... + a_{n} \cdot b_{n} = 0$. All must be nonzero as well as are, and also must not exceed by absolute value. Please find required seals for every room there.
Input
The first line contains the only integer () standing for the number of rooms in the Orochimaru's lair. The other lines contain descriptions of the doors.
Each description starts with the line containing the only even integer () denoting the number of seals.
The following line contains the space separated sequence of nonzero integers , , ..., (, ) denoting the energies of seals.
Output
For each door print a space separated sequence of nonzero integers , , ..., (, ) denoting the seals that can open the door. If there are multiple valid answers, print any. It can be proven that at least one answer always exists.
Note
For the first door Naruto can use energies . The required equality does indeed hold: .
For the second door Naruto can use, for example, energies . The required equality also holds: $1 \cdot 1 + 2 \cdot 1 + 3 \cdot 1 + 6 \cdot (-1) = 0$.
Samples
2
2
1 100
4
1 2 3 6
-100 1
1 1 1 -1
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