わたしの部屋

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#define _CRT_SECURE_NO_WARNINGS
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#include <iostream>
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using namespace std;
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long long reverse(long long n) {
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long long rev = 0;
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while (n > 0) {
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int digit = n % 10;
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rev = rev * 10 + digit;
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n /= 10;
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}
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return rev;
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}
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bool isPalindrome(long long n) {
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long long rev = reverse(n);
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return n == rev;
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}
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int main() {
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int T;
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cin >> T;
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while (T--) {
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long long n;
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int k;
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cin >> n >> k;
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bool found = false;
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int steps = 0;
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for (int i = 0; i < k; i++) {
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long long nx = reverse(n);
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long long temp = n + nx;
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if (isPalindrome(temp)) {
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n = temp;
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steps = i + 1;
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found = true;
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break;
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}
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n = temp;
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}
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if (found) {
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cout << n << " " << steps << endl;
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}
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else {
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cout << n << " " << -1 << endl;
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}
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}
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return 0;
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}

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import java.math.BigInteger;
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import java.util.Scanner;
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public class Main {
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public static BigInteger reverse(BigInteger n) {
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String str = n.toString();
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StringBuilder sb = new StringBuilder();
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for (int i = str.length() - 1; i >= 0; i--) {
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sb.append(str.charAt(i));
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}
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int st = 0;
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while (st < sb.length() - 1 && sb.charAt(st) == '0') {
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st++;
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}
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return new BigInteger(sb.substring(st));
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}
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public static boolean isPalindrome(BigInteger n) {
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String str = n.toString();
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int l = 0;
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int r = str.length() - 1;
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while (l < r) {
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if (str.charAt(l) != str.charAt(r)) {
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return false;
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}
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l++;
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r--;
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}
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return true;
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}
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public static void main(String[] args) {
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Scanner scanner = new Scanner(System.in);
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int T = scanner.nextInt();
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for (int t = 0; t < T; t++) {
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BigInteger n = scanner.nextBigInteger();
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int k = scanner.nextInt();
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boolean found = false;
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int steps = 0;
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if (isPalindrome(n)) {
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System.out.println(n + " 0");
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continue;
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}
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for (int i = 0; i < k; i++) {
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BigInteger reversed = reverse(n);
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n = n.add(reversed);
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steps = i + 1;
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if (isPalindrome(n)) {
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found = true;
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break;
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}
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}
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if (found) {
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System.out.println(n + " " + steps);
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} else {
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System.out.println(n + " -1");
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}
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}
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}
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}