there integer array perm permutation n positive integer n oddIt encode integer array encode length n 1 encodedi permi XOR permi 1 for example perm 132 encode 21given encode array return original array perm it guarantee answer exist unique Example 1input encode 31output 123explanation if perm 123 encode 1 xor 22 xor 3 31example 2input encode 6546output 24153 Constraints3 n 105n oddencodedlength n 1