|
| 1 | +class Solution { |
| 2 | + |
| 3 | + fun numberOfGoodPaths(vals: IntArray, edges: Array<IntArray>): Int { |
| 4 | + if (edges.size == 0) return vals.size |
| 5 | + |
| 6 | + var numberOfGoodPaths = vals.size |
| 7 | + val roots = IntArray(vals.size) { it } |
| 8 | + val counts = Array(vals.size) { mutableMapOf(vals[it] to 1) } |
| 9 | + val sortedEdges = edges.sortedBy { maxOf(vals[it[0]], vals[it[1]]) } |
| 10 | + |
| 11 | + sortedEdges.forEach { (from, to) -> |
| 12 | + var rootOfFrom = from |
| 13 | + var rootOfTo = to |
| 14 | + val value = maxOf(vals[from], vals[to]) |
| 15 | + |
| 16 | + while (rootOfFrom != roots[rootOfFrom]) rootOfFrom = roots[rootOfFrom] |
| 17 | + while (rootOfTo != roots[rootOfTo]) rootOfTo = roots[rootOfTo] |
| 18 | + |
| 19 | + roots[from] = rootOfFrom |
| 20 | + roots[to] = rootOfTo |
| 21 | + |
| 22 | + if (rootOfFrom != rootOfTo) { |
| 23 | + val countInFrom = counts[rootOfFrom][value] ?: 0 |
| 24 | + val countInTo = counts[rootOfTo][value] ?: 0 |
| 25 | + |
| 26 | + roots[rootOfFrom] = rootOfTo |
| 27 | + counts[rootOfTo][value] = countInFrom + countInTo |
| 28 | + numberOfGoodPaths += countInFrom * countInTo |
| 29 | + } |
| 30 | + } |
| 31 | + |
| 32 | + return numberOfGoodPaths |
| 33 | + } |
| 34 | + |
| 35 | +} |
0 commit comments