{"problem":{"name":"Diverse Word","description":{"content":"Gotou just received a dictionary. However, he doesn't recognize the language used in the dictionary. He did some analysis on the dictionary and realizes that the dictionary contains all possible **div","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"agc022_a"},"statements":[{"statement_type":"Markdown","content":"Gotou just received a dictionary. However, he doesn't recognize the language used in the dictionary. He did some analysis on the dictionary and realizes that the dictionary contains all possible **diverse** words in lexicographical order.\nA word is called **diverse** if and only if it is a nonempty string of English lowercase letters and all letters in the word are distinct. For example, `atcoder`, `zscoder` and `agc` are diverse words while `gotou` and `connect` aren't diverse words.\nGiven a diverse word $S$, determine the next word that appears after $S$ in the dictionary, i.e. the lexicographically smallest diverse word that is lexicographically larger than $S$, or determine that it doesn't exist.\nLet $X = x_{1}x_{2}...x_{n}$ and $Y = y_{1}y_{2}...y_{m}$ be two distinct strings. $X$ is lexicographically larger than $Y$ if and only if $Y$ is a prefix of $X$ or $x_{j} > y_{j}$ where $j$ is the smallest integer such that $x_{j} \\neq y_{j}$.\n\n## Constraints\n\n*   $1 \\leq |S| \\leq 26$\n*   $S$ is a diverse word.\n\n## Input\n\nInput is given from Standard Input in the following format:\n\n$S$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"agc022_a","tags":[],"sample_group":[["atcoder","atcoderb\n\n`atcoderb` is the lexicographically smallest diverse word that is lexicographically larger than `atcoder`. Note that `atcoderb` is lexicographically smaller than `b`."],["abc","abcd"],["zyxwvutsrqponmlkjihgfedcba","\\-1\n\nThis is the lexicographically largest diverse word, so the answer is `-1`."],["abcdefghijklmnopqrstuvwzyx","abcdefghijklmnopqrstuvx"]],"created_at":"2026-03-03 11:01:14"}}