На входе файл input.txt, на выходе вот что:
рот тор
о о
рот тор
о о
тот тот
о о
тот тот
тот тот
package com.javarush.task.task22.task2207;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
/*
Обращенные слова
*/
public class Solution {
public static List<Pair> result = new LinkedList<>();
public static void main(String[] args) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
FileReader fileReader = new FileReader(reader.readLine());
reader.close();
StringBuilder sb = new StringBuilder();
int input;
while ((input = fileReader.read()) != -1) {
sb.append((char) input);
}
ArrayList<String> strings = new ArrayList<>(Arrays.asList(sb.toString().split("[ \r\n]")));
// for (String s :strings) {
// System.out.println(s);
// }
for (int i = 0; i < strings.size(); i++) {
String string = strings.get(i);
if (string.isEmpty()) continue;
String reverseString = new StringBuilder(string).reverse().toString();
// System.out.printf("string: %s, reverse: %s\n", string, reverseString);
for (int j = i + 1; j < strings.size(); j++) {
String string1 = strings.get(j);
if (string1.equals(reverseString)) {
result.add(new Pair(string, reverseString));
strings.remove(i);
strings.remove(j - 1);
// i += 2;
break;
}
}
}
for (Pair pair :result) {
System.out.println(pair);
}
}
public static class Pair {
String first;
String second;
public Pair(String first, String second) {
this.first = first;
this.second = second;
}
public Pair() {
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Pair pair = (Pair) o;
if (first != null ? !first.equals(pair.first) : pair.first != null) return false;
return second != null ? second.equals(pair.second) : pair.second == null;
}
@Override
public int hashCode() {
int result = first != null ? first.hashCode() : 0;
result = 31 * result + (second != null ? second.hashCode() : 0);
return result;
}
@Override
public String toString() {
return first == null && second == null ? "" :
first == null && second != null ? second :
second == null && first != null ? first :
first.compareTo(second) < 0 ? first + " " + second : second + " " + first;
}
}
}