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char - How to get character's position in alphabet in C language?

Is there a quick way to retrieve given character's position in the english alphabet in C?

Something like:

int position = get_position('g');
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int position = 'g' - 'a' + 1;

In C, char values are convertible to int values and take on their ASCII values. In this case, 'a' is the same as 97 and 'g' is 103. Since the alphabet is contiguous within the ASCII character set, subtracting 'a' from your value gives its relative position. Add 1 if you consider 'a' to be the first (instead of zeroth) position.


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