Пишет, что находит слов больше нужного.
package com.javarush.task.task19.task1907;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Solution {
public static void main(String[] args) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
BufferedReader fileReader = new BufferedReader(new FileReader(reader.readLine()));
StringBuilder line = new StringBuilder();
while (fileReader.ready()) {
line.append(fileReader.readLine());
}
Pattern p = Pattern.compile("world");
Matcher m = p.matcher(line);
int i = 0;
while (m.find()) {
i++;
}
System.out.println(i);
reader.close();
fileReader.close();
}
}