##Ruby##

Everyone knows: sorting is very slow and takes many cycles (the best you can do is something with `n log(n)`). Thus it is quite easy to check if the array is sorted. All you have to do is compare the runtime of sorting the array and sorting the sorted array.

 array = [1, 5, 4, 2, 3]
 
 ## measure the time needed to sort the array 1m times
 tstart = Time.now
 1000000.times {
 array.sort
 }
 trun = Time.now - tstart
 
 ## now do a reference measurement on a sorted array
 array.sort!
 tstart = Time.now
 1000000.times {
 array.sort
 }
 treference = Time.now - tstart
 
 ## compare run times
 if trun > treference
 print "array was not sorted"
 else
 print "array was sorted"
 end