Alex has a string S(the first character of S is S0, the second is S1 and so on) but the string is normal. As we all know, Alex is a naughty boy, now he wants to change the string, we know the length of S is n and n is an even number, now he wants to swap (S0, S1), (S2, S3), ..., (Sn-1, Sn), please tell him the string after swaping.
For each test case, print the string after swaping.
For the first sample, we swap (a, b) (c, d) (1, 2) (3, 4), then we can get string "badc2143".