题解 | #小红的字符串构造#
小红的字符串构造
https://www.nowcoder.com/practice/3e4b4dabc2e444e384c3ae62ac7dd84e
import java.io.*; import java.util.*; import java.math.BigInteger; public class Main { static void solve() { String s = in.next(); LinkedHashSet<Character> set = new LinkedHashSet<>(); for(char c : s.toCharArray()){ set.add(c); } if(set.size()==1) { out.println(-1); }else { ArrayList<Character> list = new ArrayList<>(set); HashMap<Character,Character> map = new HashMap<>(); int sz = list.size(); for(int i=0;i<sz;i++) { char x = list.get(i); char y = list.get((i+1)%sz); map.put(x,y); } StringBuilder t = new StringBuilder(); for(char c: s.toCharArray()) { t.append(map.get(c)); } out.println(t); } } public static void main(String[] args) { solve(); out.flush(); } static FastReader in = new FastReader(); static PrintWriter out = new PrintWriter(System.out); static class FastReader { static BufferedReader br; static StringTokenizer st; FastReader() { br = new BufferedReader(new InputStreamReader(System.in)); } String next() { String str = ""; while(st==null||!st.hasMoreElements()) { try { str = br.readLine(); }catch(IOException e) { throw new RuntimeException(e); } st = new StringTokenizer(str); } return st.nextToken(); } int nextInt() { return Integer.parseInt(next()); } double nextDouble() { return Double.parseDouble(next()); } long nextLong() { return Long.parseLong(next()); } } }