package com.klvchen.exer;
import org.junit.Test;
import java.util.Arrays;
public class StringDemo2 {
/*
获取两个字符串中最大相同子串,比如:
str1 = "abcwerthelloyuiodef" ; str2 = "cvhellobnm"
提示:将短的那个串进行长度依次递减的子串与较长的串比较。
*/
public String getMaxSameString(String str1, String str2){
String maxStr = (str1.length() >= str2.length())? str1 : str2;
String minStr = (str1.length() < str2.length())? str1 : str2;
int length = minStr.length();
for (int i = 0; i < length; i++){
for (int x = 0, y = length - i; y <= length; x++, y++){
String subStr = minStr.substring(x, y);
if (maxStr.contains(subStr)){
return subStr;
}
}
}
return null;
}
// 如果存在多个长度相同的最大相同子串
// 此时先返回 String[], 后面可以用集合中的 ArrayList 替换,较方便
public String[] getMaxSameString1(String str1, String str2){
if (str1 != null && str2 != null){
StringBuffer sBuffer = new StringBuffer();
String maxString = (str1.length() > str2.length()) ? str1 : str2;
String minString = (str1.length() > str2.length()) ? str2 : str1;
int len = minString.length();
for (int i = 0; i < len; i++){
for (int x = 0, y = len - i; y <= len; x++, y++){
String subString = minString.substring(x, y);
if (maxString.contains(subString)){
sBuffer.append(subString + ",");
}
}
// System.out.println(sBuffer);
if (sBuffer.length() != 0){
break;
}
}
String[] split = sBuffer.toString().replaceAll(",$", "").split("\\,");
return split;
}
return null;
}
@Test
public void testGetMaxSameString(){
String str1 = "abcwerthelloyuiodef";
String str2 = "cvhellobnm";
String[] maxSameStrings = getMaxSameString1(str1, str2);
System.out.println(Arrays.toString(maxSameStrings));
}
}
![](https://img2020.cnblogs.com/blog/1334255/202109/1334255-20210902195011983-682615066.png)