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CSES Problemset/Introductory Problems

String Reorder

#1743
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Your task is to reorder the characters of a string so that no two adjacent characters are the same. What is the lexicographically minimal such string?

Input

The only line has a string of length nn consisting of characters A–Z.

Output

Print the lexicographically minimal reordered string where no two adjacent characters are the same. If it is not possible to create such a string, print −1-1.

Constraints
  • 1≤n≤1061 \le n \le 10^6
Sample Test Cases (1)
Example 1ID: sample-1
Input
HATTIVATTI
Expected Output
AHATITITVT
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Test Bench
Download .zip
Input (stdin)
HATTIVATTI
Expected Output
AHATITITVT