Lately, YuPenG the Penguin has been playing too much mousehunt during class and even got to the rank of grand duke. At one point, the magical sun, moon and star transform YuPenG from a Penguin to a mouse! Squeak! Oh no! Now, to satisfy his intense hunger for cheese, YuPenG has to eat two pieces of cheese a day. Squeak! He then caught a whiff of the smell of cheese coming from Damian's camp. Squeak! He sneaked into Damian's camp to find a row of pieces of cheese. Squeak! Each of these cheeses has a tasty value of coincidentally, as Damian loves math so much, all values of are prime () and all values are unique.
Squeak! Also, the cheeses are all arranged in sorted order in a row from left to right. YuPenG starts at the far left of the row. Squeak! However, being the lazy mouse that he is, he can only run up to the th cheese where is less than or equal to and he can only take two pieces of cheese that are adjacent to each other. Squeak! Also, being the math god, he will only eat the two-adjacent cheese if the sum of their values, cannot be expressed as where . Squeak! Having so many different choices of cheeses to choose from, YuPenG is wondering exactly how many and what are the pairs he can take for some . Squeak! Since YuPenG wishes to give some chance and allow others to do the math for him, he asked you to help him find the options that he has for different queries of . Squeak!
Input Specification
The first line of input will contain one integer, . The next lines will each contain one integer representing .
Output Specification
The output should contain lines. Each line should contain the pairs which YuPenG can choose, and the pairs should be in the format of with spaces between pairs. If no valid pair exists, output -1
.
Constraints
Sample Input
1
5
Sample Output
(2,3)
Explanation for Sample Output
YuPenG can only move to the cheese which has a value less than or equal to so he can only move to cheeses , and and the only pairs are and . cannot be expressed as any so YuPenG can eat this pair. However, can be expressed as , thus YuPenG will not eat this pair.
Important Note
If you're using cin/cout, increase I/O speed by placing the following code at the start of your main function:
ios_base::sync_with_stdio(false);
cin.tie(0);
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