Lean4

53. Reverse the words

EasyProgramFree10 points

Write reverseWords s: the words of s in reverse order, separated by single spaces. Words are separated by one or more spaces, and s may start or end with spaces, which do not appear in the result.

Examples

  1. InputreverseWords "the sky is blue"Output"blue is sky the"
  2. InputreverseWords " hello world "Output"world hello"

Submitting also runs 5 hidden tests.

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Solution.lean
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3#guard (reverseWords "the sky is blue") = ("blue is sky the")
4#guard (reverseWords " hello world ") = ("world hello")
examples

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