There is a hidden string of length n composed of the first m lowercase English letters. For any two different English letters, we will tell you a subsequence of the hidden string constructed by removing all other letters from the hidden string.For example, if the hidden string is "apple" and the chosen letters are 'e' and 'p', the resulting subsequence would be "ppe"; if the chosen letters are 'a' and 'x', the resulting subsequence would be "a".Now, please recover the hidden string. Output -1 if there are no possible hidden string. Output any one if there are multiple possible hidden strings.
There is a hidden string of length n composed of the first m lowercase English letters. For any two different English letters, we will tell you a subsequence of the hidden string constructed by removing all other letters from the hidden string. For example, if the hidden string is "apple" and the chosen letters are 'e' and 'p', the resulting subsequence would be "ppe"; if the chosen letters are 'a' and 'x', the resulting subsequence would be "a". Now, please recover the hidden string. Output -1 if there are no possible hidden string. Output any one if there are multiple possible hidden strings.
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