Edit Distance 最小编辑距离

概述

Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.)

You have the following 3 operations permitted on a word:

a) Insert a character 
b) Delete a character 
c) Replace a character

思路

动态规划

代码

package com.lilei.spring_boot_db.boot.pack1115;

public class edit_distance {

	public static void main(String[] args) {
		System.out.println(min_distance("asdfvvvvsds","assdfvvvvsdsds"));
	}

	static int min_distance(String src, String dest) {

		if (src.length() >0 && dest.length() >0) {
			char c1 = src.charAt(src.length() - 1);
			char c2 = dest.charAt(dest.length() - 1);
			int dest_delete = min_distance(src,
					dest.substring(0, dest.length() - 1)) + 1;
			int src_delete = min_distance(src.substring(0, src.length() - 1),
					dest) + 1;
			int both_delete = -1;
			if (c1 == c2) {
				both_delete = min_distance(src.substring(0, src.length() - 1),
						dest.substring(0, dest.length() - 1));
			} else {

				both_delete = min_distance(src.substring(0, src.length() - 1),
						dest.substring(0, dest.length() - 1)) + 2;

			}
			return Math.min(dest_delete, Math.min(src_delete, both_delete));
		}else{
			if (src.length() == 0){
				return dest.length();
			}else{
				return src.length();
			}
		}
	}

}