Check if each letter $i$ in the range $0, S/2$, where $S$ is the size of the word, is equal to its corresponding letter ($S-i-1$). If it isn’t, then break the loop early and print NAY otherwise print YAY after searching the whole word.

Time complexity

$\mathcal{O}(S)$, where $S$ is the length of the word.

Problem

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