Java练习题-输入一个字符串，如何求最大重复出现的字符串（） Java练习题-输入一个字符串，如

比如输入 ttabcftrgabcd,输出结果为 abc， canffcancd,输出结果为 can。
下面是解题代码：

import java.util.HashMap; import java.util.Map; /** * 输入一个字符串，如何求最长的重复出现的字符串？ * 比如输入 ttabcftrgabcd,输出结果为 abc， canffcancd,输出结果为 can。 * * @author Tang */ public class Test {public static void main(String[] args) { System.out.println("ttabcftrgabcd中最长的重复字符串:" + computeMaxRepeatString("ttabcftrgabcd")); System.out.println("canffcancd中最长的重复字符串:" + computeMaxRepeatString("canffcancd")); System.out.println(); System.out.println("A中最长的重复字符串:" + computeMaxRepeatString("A")); System.out.println("AB中最长的重复字符串:" + computeMaxRepeatString("AB")); System.out.println(); System.out.println("ABCDBCD中最长的重复字符串:" + computeMaxRepeatString("ABCDBCD")); System.out.println("ABCDBCDCD中最长的重复字符串:" + computeMaxRepeatString("ABCDBCDCD")); System.out.println(); System.out.println("ABCDABCDCD中最长的重复字符串:" + computeMaxRepeatString("ABCDABCDCD")); System.out.println("ABCDABCDBCDCD中最长的重复字符串:" + computeMaxRepeatString("ABCDABCDBCDCD")); }/** * 计算最长的重复字符串 * * @param str * @return */ public static String computeMaxRepeatString(String str) {String maxNumberKey = null; Integer maxNumberNumber = 0; int len = str.length(); if (len < 1) { throw new RuntimeException("string is empty"); }if (len < 2) { return str.charAt(0) + ""; }for (int i = 2; i <= len; i++) {//i = 2意思是至少两个字符才开始算字符串Object[] maxValue = https://www.it610.com/article/computeMaxRepeatString(str, i); String numberKey = (String) maxValue[0]; Integer numberNumber = (Integer) maxValue[1]; if (numberNumber>= maxNumberNumber || numberNumber >= 2) { maxNumberKey = numberKey; maxNumberNumber = numberNumber; } } return maxNumberKey; }private static Object[] computeMaxRepeatString(String str, int count) {Map numberMap = new HashMap<>(); String maxNumberKey = null; Integer maxNumberNumber = 0; for (int i = 0; i <= str.length() - count; i++) {String temp = str.substring(i, i + count); Integer charNumber = numberMap.get(temp); if (charNumber == null) { charNumber = 1; } else { charNumber++; } numberMap.put(temp, charNumber); if (maxNumberKey == null) { maxNumberKey = temp; maxNumberNumber = charNumber; } else { if (charNumber > maxNumberNumber) { maxNumberKey = temp; maxNumberNumber = charNumber; } } } return new Object[] { maxNumberKey, maxNumberNumber }; } }

打印结果：
ttabcftrgabcd中最长的重复字符串:abc
canffcancd中最长的重复字符串:can
A中最长的重复字符串:A
AB中最长的重复字符串:AB
ABCDBCD中最长的重复字符串:BCD
ABCDBCDCD中最长的重复字符串:BCD
ABCDABCDCD中最长的重复字符串:ABCD
ABCDABCDBCDCD中最长的重复字符串:ABCD
【Java练习题-输入一个字符串，如何求最大重复出现的字符串（）】转载于:https://my.oschina.net/tangzhichao/blog/781467