70 lines
1.9 KiB
Swift
70 lines
1.9 KiB
Swift
|
var input: [(from: String, to: String, distance: Int)] = [
|
||
|
|
("Tristram", "AlphaCentauri", 34),
|
||
|
|
("Tristram", "Snowdin", 100),
|
||
|
|
("Tristram", "Tambi", 63),
|
||
|
|
("Tristram", "Faerun", 108),
|
||
|
|
("Tristram", "Norrath", 111),
|
||
|
|
("Tristram", "Straylight", 89),
|
||
|
|
("Tristram", "Arbre", 132),
|
||
|
|
("AlphaCentauri", "Snowdin", 4),
|
||
|
|
("AlphaCentauri", "Tambi", 79),
|
||
|
|
("AlphaCentauri", "Faerun", 44),
|
||
|
|
("AlphaCentauri", "Norrath", 147),
|
||
|
|
("AlphaCentauri", "Straylight", 133),
|
||
|
|
("AlphaCentauri", "Arbre", 74),
|
||
|
|
("Snowdin", "Tambi", 105),
|
||
|
|
("Snowdin", "Faerun", 95),
|
||
|
|
("Snowdin", "Norrath", 48),
|
||
|
|
("Snowdin", "Straylight", 88),
|
||
|
|
("Snowdin", "Arbre", 7),
|
||
|
|
("Tambi", "Faerun", 68),
|
||
|
|
("Tambi", "Norrath", 134),
|
||
|
|
("Tambi", "Straylight", 107),
|
||
|
|
("Tambi", "Arbre", 40),
|
||
|
|
("Faerun", "Norrath", 11),
|
||
|
|
("Faerun", "Straylight", 66),
|
||
|
|
("Faerun", "Arbre", 144),
|
||
|
|
("Norrath", "Straylight", 115),
|
||
|
|
("Norrath", "Arbre", 135),
|
||
|
|
("Straylight", "Arbre", 127),
|
||
|
|
]
|
||
|
|
|
||
|
|
var distances: [String: [String: Int]] = input.reduce(into: [:]) { result, input in
|
||
|
|
let (from, to, distance) = input
|
||
|
|
|
||
|
|
result[from, default: [:]][to] = distance
|
||
|
|
result[to, default: [:]][from] = distance
|
||
|
|
}
|
||
|
|
|
||
|
|
func totalDistance(route: [String]) -> Int {
|
||
|
|
var distance = 0
|
||
|
|
var current = route[0]
|
||
|
|
for place in route.dropFirst() {
|
||
|
|
distance += distances[current]![place]!
|
||
|
|
current = place
|
||
|
|
}
|
||
|
|
|
||
|
|
return distance
|
||
|
|
}
|
||
|
|
|
||
|
|
func combinations(_ s: Set<String>) -> [[String]] {
|
||
|
|
if s.count <= 2 {
|
||
|
|
return [Array(s)]
|
||
|
|
}
|
||
|
|
|
||
|
|
return s.reduce([]) { result, first in
|
||
|
|
let rest = s.subtracting([first])
|
||
|
|
|
||
|
|
return result + combinations(rest).map { sub in
|
||
|
|
var result = [first]
|
||
|
|
result.append(contentsOf: sub)
|
||
|
|
return result
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
combinations(Set(distances.keys))
|
||
|
|
.map { totalDistance(route: $0) }
|
||
|
|
.max()
|
||
|
|
|