64 lines
2.1 KiB
Java
64 lines
2.1 KiB
Java
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import java.nio.file.Files;
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import java.nio.file.Path;
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class solution {
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private interface DigitFinder {
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int getDigit(String s, int idx);
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}
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private static int parseDigits(DigitFinder df, String s) {
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int a = -1, b = -1;
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for (int i = 0; i < s.length(); i++) {
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int an = df.getDigit(s, i);
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int bn = df.getDigit(s, s.length() - i - 1);
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if (a == -1 && an != -1) a = an;
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if (b == -1 && bn != -1) b = bn;
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if (a != -1 && b != -1) break;
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}
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return a * 10 + b;
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}
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private static class Part1DigitFinder implements DigitFinder {
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public int getDigit(String s, int idx) {
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if (Character.isDigit(s.charAt(idx))) {
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return s.charAt(idx) - '0';
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}
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return -1;
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}
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}
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private static void part1() throws Exception {
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var df = new Part1DigitFinder();
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int sum = Files.readAllLines(Path.of("part_1_input.txt")).stream()
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.mapToInt(line -> parseDigits(df, line))
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.sum();
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System.out.println(sum);
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}
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private static class Part2DigitFinder implements DigitFinder {
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public int getDigit(String s, int idx) {
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if (Character.isDigit(s.charAt(idx))) return s.charAt(idx) - '0';
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String[] words = {"one", "two", "three", "four", "five", "six", "seven", "eight", "nine"};
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for (int i = 0; i < words.length; i++) {
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String word = words[i];
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if (s.length() - idx >= word.length() && s.substring(idx, idx + word.length()).equals(word)) {
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return i + 1;
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}
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}
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return -1;
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}
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}
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private static void part2() throws Exception {
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var df = new Part2DigitFinder();
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int sum = Files.readAllLines(Path.of("part_2_input.txt")).stream()
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.mapToInt(line -> parseDigits(df, line))
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.sum();
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System.out.println(sum);
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}
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public static void main(String[] args) throws Exception {
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part1();
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part2();
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}
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}
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