The local commuter railroad services a number of towns in Kiwiland. Because of monetary concerns, all of the tracks are 'one-way.' That is, a route from Kaitaia to Invercargill does not imply the existence of a route from Invercargill to Kaitaia. In fact,
npm install challange-trains
The purpose of this problem is to help the railroad provide its customers with information about the routes. In particular, you will compute the distance along a certain route, the number of different routes between two towns, and the shortest route between two towns.
#### Input
A directed graph where a node represents a town and an edge represents a route between two towns. The weighting of the edge represents the distance between the two towns. A given route will never appear more than once, and for a given route, the starting and ending town will not be the same town.
#### Output
For test input 1 through 5, if no such route exists, output 'NO SUCH ROUTE'. Otherwise, follow the route as given; do not make any extra stops! For example, the first problem means to start at city A, then travel directly to city B (a distance of 5), then directly to city C (a distance of 4).
#### Problems:
1. The distance of the route A-B-C.
2. The distance of the route A-D.
3. The distance of the route A-D-C.
4. The distance of the route A-E-B-C-D.
5. The distance of the route A-E-D.
#### Test Input:
For the test input, the towns are named using the first few letters of the alphabet from A to D. A route between two towns (A to B) with a distance of 5 is represented as AB5.
Graph: AB5, BC4, CD8, DC8, DE6, AD5, CE2, EB3, AE7
#### Expected Output:
- Output #1: 9
- Output #2: 5
- Output #3: 13
- Output #4: 22
- Output #5: NO SUCH ROUTE
``
$ npm install challange-trains
`js
const Graphs = require('challange-trains')
// initialize
const Trains = new Graphs({
A: {
B: 5,
E: 7
},
B: {
C: 4
},
C: {
D: 8
}
})
// calculate distance for a given route
Trains.calculateDistance('A', 'B', 'C') // Output: 9
Trains.calculateDistance('A', 'E') // Output: 7
Trains.calculateDistance('A', 'C') // throws new Error('NO SUCH ROUTE')
`
`
// inside the repository
$ npm install
$ npm run test
MIT © Grzegorz Leoniec (@WillKnowThat)