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Check if a string consists of a repeated character sequence

Written byPhuoc Nguyen
21 Apr, 2021
Last updated
13 Oct, 2021
JavaScript version
const consistsRepeatedSubstring = (str) => `${str}${str}`.indexOf(str, 1) !== str.length;
TypeScript version
const consistsRepeatedSubstring = (str: string): boolean => `${str}${str}`.indexOf(str, 1) !== str.length;
consistsRepeatedSubstring('aa'); // true
consistsRepeatedSubstring('aaa'); // true
consistsRepeatedSubstring('ababab'); // true
consistsRepeatedSubstring('abc'); // false

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