look up city by letters..
look up city by letters..

(before:)

$ time ./a.out < data_300.txt
BRE
300 0

real	0m22.085s
user	0m22.020s
sys	0m0.064s

(after:)

$ time ./a.out < data_300.txt
BRE
300

real	0m2.570s
user	0m2.536s
sys	0m0.032s

RoadToSoftwareFactory/UnaMosca,RoadToSoftwareFactory/UnaMosca,RoadToSoftwareFactory/UnaMosca