If the performance improves i.e., {HEAD ~ the objective function value} is lower at {TAIL ~ the trial solution} than at the best solution found so far, exit 
If the performance improves i.e. , { HEAD ~ the objective function value } is lower at { TAIL ~ the trial solution } than at the best solution found so far , exit
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH