Hi, I am freshman on this group. I think many of you can help me on programming scheme :)) because I am beginner but I can understand when I see how coded a question. and this helps me be good at scheme.
> For example wanna make sth like that; > > ( ) > > ( ) > Database: > > (define flights > ‘((f237 istanbul frankfurt 5) > (f220 newyork frankfurt 10) > (f225 newyork paris 15) > (f110 berlin moscow 6) > (f050 istanbul moscow 3) > (f105 frankfurt istanbul 5) > (f023 istanbul tehran 4) > (f338 tehran paris 7) > (f461 frankfurt paris 2) > (f173 frankfurt newyork 10) > (f290 paris newyork 15) > (f190 moscow paris 5) > (f320 paris tehran 7) > (f240 newyork moscow 18))) > > (define passengers > ‘((jake istanbul frankfurt) > (mike newyork istanbul) > (pier istanbul berlin) > (hans frankfurt moscow) > (john newyork istanbul))) > I want to implement the function find-flight which takes source and > destination as input (2 parameters) and returns flight number as a > list with one element or nothing if no such flight exists. > > > (find-flight 'istanbul 'frankfurt) > (list 'f237) > > (find-flight 'tehran 'istanbul) > empty > > For example, I wanna implement the function shortest-travel which > takes passenger as input and returns a list of flight numbers which > is the travel alternative with the smallest total flight > time. Again, you do not need to consider travel alternatives with > more than one transit > > > (shortest-travel 'jake) > (list ‘f237) > > (shortest-travel 'john) > (list ‘f220 ‘f105) > > (shortes-travel 'pier) > (list 'f220 'f461) > > If you help me, you will make a great favour to me :))
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