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add stick to chosen route when re-routing with ui functionality
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.../java/com/mapbox/services/android/navigation/ui/v5/route/DamerauLevenshteinAlgorithm.java
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| package com.mapbox.services.android.navigation.ui.v5.route; | ||
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| import java.util.HashMap; | ||
| import java.util.Map; | ||
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| /* Copyright (c) 2012 Kevin L. Stern | ||
| * | ||
| * Permission is hereby granted, free of charge, to any person obtaining a copy | ||
| * of this software and associated documentation files (the "Software"), to deal | ||
| * in the Software without restriction, including without limitation the rights | ||
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | ||
| * copies of the Software, and to permit persons to whom the Software is | ||
| * furnished to do so, subject to the following conditions: | ||
| * | ||
| * The above copyright notice and this permission notice shall be included in | ||
| * all copies or substantial portions of the Software. | ||
| * | ||
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | ||
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | ||
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | ||
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | ||
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | ||
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | ||
| * SOFTWARE. | ||
| */ | ||
|
|
||
| /** | ||
| * The Damerau-Levenshtein Algorithm is an extension to the Levenshtein | ||
| * Algorithm which solves the edit distance problem between a source string and | ||
| * a target string with the following operations: | ||
| * <p> | ||
| * <ul> | ||
| * <li>Character Insertion</li> | ||
| * <li>Character Deletion</li> | ||
| * <li>Character Replacement</li> | ||
| * <li>Adjacent Character Swap</li> | ||
| * </ul> | ||
| * <p> | ||
| * Note that the adjacent character swap operation is an edit that may be | ||
| * applied when two adjacent characters in the source string match two adjacent | ||
| * characters in the target string, but in reverse order, rather than a general | ||
| * allowance for adjacent character swaps. | ||
| * <p> | ||
| * <p> | ||
| * This implementation allows the client to specify the costs of the various | ||
| * edit operations with the restriction that the cost of two swap operations | ||
| * must not be less than the cost of a delete operation followed by an insert | ||
| * operation. This restriction is required to preclude two swaps involving the | ||
| * same character being required for optimality which, in turn, enables a fast | ||
| * dynamic programming solution. | ||
| * <p> | ||
| * <p> | ||
| * The running time of the Damerau-Levenshtein algorithm is O(n*m) where n is | ||
| * the length of the source string and m is the length of the target string. | ||
| * This implementation consumes O(n*m) space. | ||
| * | ||
| * @author Kevin L. Stern | ||
| */ | ||
| class DamerauLevenshteinAlgorithm { | ||
| private static final int DELETE_COST = 1; | ||
| private static final int INSERT_COST = 1; | ||
| private static final int REPLACE_COST = 1; | ||
| private static final int SWAP_COST = 1; | ||
|
|
||
| /** | ||
| * Compute the Damerau-Levenshtein distance between the specified source | ||
| * string and the specified target string. | ||
| */ | ||
| static int execute(String source, String target) { | ||
| if (source.length() == 0) { | ||
| return target.length() * INSERT_COST; | ||
| } | ||
| if (target.length() == 0) { | ||
| return source.length() * DELETE_COST; | ||
| } | ||
| int[][] table = new int[source.length()][target.length()]; | ||
| Map<Character, Integer> sourceIndexByCharacter = new HashMap<>(); | ||
| if (source.charAt(0) != target.charAt(0)) { | ||
| table[0][0] = Math.min(REPLACE_COST, DELETE_COST + INSERT_COST); | ||
| } | ||
| sourceIndexByCharacter.put(source.charAt(0), 0); | ||
| for (int i = 1; i < source.length(); i++) { | ||
| int deleteDistance = table[i - 1][0] + DELETE_COST; | ||
| int insertDistance = (i + 1) * DELETE_COST + INSERT_COST; | ||
| int matchDistance = i * DELETE_COST + (source.charAt(i) == target.charAt(0) ? 0 : REPLACE_COST); | ||
| table[i][0] = Math.min(Math.min(deleteDistance, insertDistance), matchDistance); | ||
| } | ||
| for (int j = 1; j < target.length(); j++) { | ||
| int deleteDistance = (j + 1) * INSERT_COST + DELETE_COST; | ||
| int insertDistance = table[0][j - 1] + INSERT_COST; | ||
| int matchDistance = j * INSERT_COST + (source.charAt(0) == target.charAt(j) ? 0 : REPLACE_COST); | ||
| table[0][j] = Math.min(Math.min(deleteDistance, insertDistance), matchDistance); | ||
| } | ||
| for (int i = 1; i < source.length(); i++) { | ||
| int maxSourceLetterMatchIndex = source.charAt(i) == target.charAt(0) ? 0 : -1; | ||
| for (int j = 1; j < target.length(); j++) { | ||
| Integer candidateSwapIndex = sourceIndexByCharacter.get(target.charAt(j)); | ||
| int indexJSwap = maxSourceLetterMatchIndex; | ||
| int deleteDistance = table[i - 1][j] + DELETE_COST; | ||
| int insertDistance = table[i][j - 1] + INSERT_COST; | ||
| int matchDistance = table[i - 1][j - 1]; | ||
| if (source.charAt(i) != target.charAt(j)) { | ||
| matchDistance += REPLACE_COST; | ||
| } else { | ||
| maxSourceLetterMatchIndex = j; | ||
| } | ||
| int swapDistance; | ||
| if (candidateSwapIndex != null && indexJSwap != -1) { | ||
| int indexISwap = candidateSwapIndex; | ||
| int preSwapCost; | ||
| if (indexISwap == 0 && indexJSwap == 0) { | ||
| preSwapCost = 0; | ||
| } else { | ||
| preSwapCost = table[Math.max(0, indexISwap - 1)][Math.max(0, indexJSwap - 1)]; | ||
| } | ||
| swapDistance = preSwapCost + (i - indexISwap - 1) * DELETE_COST + (j - indexJSwap - 1) * INSERT_COST | ||
| + SWAP_COST; | ||
| } else { | ||
| swapDistance = Integer.MAX_VALUE; | ||
| } | ||
| table[i][j] = Math.min(Math.min(Math.min(deleteDistance, insertDistance), matchDistance), swapDistance); | ||
| } | ||
| sourceIndexByCharacter.put(source.charAt(i), i); | ||
| } | ||
| return table[source.length() - 1][target.length() - 1]; | ||
| } | ||
| } |
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