11 lines
395 B
Ruby
11 lines
395 B
Ruby
# Assume you have a method is_substring(s1, s2) which checks if one word is a substring
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# of another string. Given 2 strings s1, s2, write code to check if s2 is a rotation
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# of s1 using only one call to is_substring. ex. waterbottle -> erbottlewat
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def string_is_substring(s1, s2)
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return false if s1.length != s2.length || s1.length == 0
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s1s1 = s1 + s1
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string_is_substring(s1s1, s2)
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end
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