Clam Card
Level: Intermediate 30–60 minConcepts: State
Implement a system for a contactless travel card for subways.
- The card does not need to be topped up.
- The card charges the owner’s bank account directly when used.
- The card is used by touching in and out at train stations.
- The train system accepting this card has two categorical zones of stations, Zone A and Zone B.
| Zone A | Zone B |
|---|---|
| Asterisk | Bison |
| Amersham | Bugel |
| Aldgate | Balham |
| Angel | Bullhead |
| Anerley | Barbican |
- Traveling within zone B is more expensive than traveling in Zone A.
- The price of zone B is inclusive of traveling within zone A.
- If one of the stations is within Zone 2 at any point in a journey, the price for zone 2 will be charged.
The fares are as described below:
| Zone | Single | Day | Week | Month |
|---|---|---|---|---|
| Zone A | $2.50 | $7.00 | $40.00 | $145.00 |
| Zone B | $3.00 | $8.00 | $47.00 | $165.00 |
- A Single is a journey from one station to another.
- A Day fare includes all single journeys made within a single day.
- A Week fare includes all single journeys made within a single week.
- A Month fare includes all single journeys made within a single month.
- No matter how many journeys are made within one of the time boundaries within a particular zone, the price will cap at that time period’s fare.
Scenarios
Follow these scenarios driving out our code as you go.
One-Way Zone 1 Journey Given Michael has a Clam Card And Michael travels from Asterisk to Aldgate Then Michael will be charged $2.50 for his first journey
One-Way Zone 1 to Zone 2 Journey Given Michael has a Clam Card And Michael travels from Asterisk to Barbican Then Michael will be charged $3.0 for his first journey
Multiple journeys Given Michael has a Clam Card And Michael travels from Asterisk to Aldgate And Michael travels from Asterisk to Balham Then Michael will be charged $2.50 for his first journey And a further $3.00 for his second journey. Totaling $5.50
Multiple Journeys including Zone B reaching daily cap Given Michael has a Clam Card And Michael travels from Asterisk to Barbican And Michael travels from Barbican to Balham And Michael travels from Balham to Bison And Michael travels from Bison to Asterisk Then Michael will be charged $3.00 for his first journey And a further $3.00 for his second journey And a further $2 for his third journey And a further $0.00 for his fourth journey
Multiple Journeys Zone A reaching daily cap Given Michael has a Clam Card And Michael travels from Asterisk to Aldgate And Michael travels from Aldgate to Angel And Michael travels from Angel to Antelope And Michael travels from Antelope to Asterisk Then Michael will be charged $2.50 for his first journey And a further $2.50 for his second journey And a further $2 for his third journey And a further $0.00 for his fourth journey
Bonus
Take into account for return journeys, the new fares are as described below:
| Zone | Single Return |
|---|---|
| Zone A | $2.00 |
| Zone B | $2.50 |
- A Single is a journey from one station to another.
- A Return is a single journey where the next immediate journey is the inverse of the previous journey.
- Traveling from station A to station B, then from Station B to station A, classifies as a return.
- A Day fare still includes all single and return journeys made within a single day.
- A Week fare still includes all single and return journeys made within a single week.
- A month fare still includes all single and return journeys made within a single month.
Multiple Return Journeys And Michael travels from Asterisk to Barbican And Michael travels from Barbican to Asterisk And Michael travels from Asterisk to Balham And Michael travels from Balham to Asterisk Then Michael will be charged $3.00 for his first journey And a further $2.50 for his second journey And a further $1.50 for his third journey And a further $0.00 for his fourth journey