monodevelop console error

[ramirobh]

Hello everyone! Well, the problem is... i did install mono develop on ubuntu 11.04 so i can study some C# without having to install any Windows, but im having the following problem:

Lets suppose that i run this code:

http://pastebin.com/vmxTnXS8

So... when i try to write the values... i have to press the number two times to make it appear on the Console/terminal ... if i just press one time, nothing happens... so lets suppose that i write this values:

vet1[0] : 1
vet2[0] : 4
vet3[0] : 7
vet1[1] : 2
vet2[1] : 5
vet3[1] : 8
vet1[2] : 3
vet2[2] : 6
vet3[2] : 9

So thats what the console should print is those values to vet1 and 2...but because of that error on the console, thats what it prints:
(it may change the values, cause sometimes i have to press the number even 3 times... so it appear just one...but prints 3 times)

vet1[0] : 11
vet2[0] : 44
vet3[0] : 7
vet1[1] : 22
vet2[1] : 55
vet3[1] : 8
vet1[2] : 33
vet2[2] : 6
vet3[2] : 9

Any idea of what is happening? How to fix it?
Thanks already for the help!