| #ifndef _PRAGMA_COPYRIGHT_ |
| #define _PRAGMA_COPYRIGHT_ |
| #pragma comment(copyright, "%Z% %I% %W% %D% %T%\0") |
| #endif /* _PRAGMA_COPYRIGHT_ */ |
| /**************************************************************************** |
| |
| * Copyright (c) 2008, 2010 IBM Corporation. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0s |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| |
| Classes: Levenshtein |
| |
| Description: Levenshtein algorithm. |
| |
| Author: Nicole Nie, Tu HongJ, Liu Wei |
| |
| History: |
| Date Who ID Description |
| -------- --- --- ----------- |
| 10/29/08 nieyy Initial code (D154050) |
| |
| ****************************************************************************/ |
| |
| #include "levenshtein.hpp" |
| |
| #include <algorithm> |
| |
| int Levenshtein::Distance(const string &s1, const string &s2) |
| { |
| int i, j, cost; |
| int n = s1.length(), m = s2.length(); |
| int *matrix = new int[(m + 1) * (n + 1)]; |
| |
| if (m == 0) |
| return n; |
| if (n == 0) |
| return m; |
| |
| m++; |
| n++; |
| |
| for (i = 0; i < n; i ++) |
| matrix[i] = i; |
| for (i = 0; i < m; i ++) |
| matrix[i * n] = i; |
| |
| for (i = 1; i < n; i ++) { |
| for (j = 1; j < m; j ++) { |
| if (s1[i - 1] == s2[j - 1]) |
| cost = 0; |
| else |
| cost = 1; |
| matrix[j * n + i] = Minimum(matrix[(j-1)*n+i]+1, matrix[j*n+i-1]+1, matrix[(j-1)*n+i-1]+cost); |
| } |
| } |
| |
| cost = matrix[n * m - 1]; |
| delete [] matrix; |
| |
| return cost; |
| } |
| |
