The sign of the modulo operator result?

Question

I have couple line of C code testing the modulo operator as follows:

// line 1
printf("%d\n", 5 % (-3)); => output: 2
// line 2
printf("%d\n", -5 % 3); => output: -2

I know that the sign of the modulo depends on the sign of the numerator, but I am curious why not otherwise?

This is not a question to vote down. It is a question of how the modulo operator works, and is a good question. — Richard J. Ross III, Feb 06 '12 at 14:43
I'm pretty sure the result of pretty much any combination of `%` and negative numbers is implementation-defined. — cHao, Feb 06 '12 at 14:48
It's implementation-defined prior to C99 - see previous duplicates — Paul R, Feb 06 '12 at 14:53

score 3 · Answer 1 · answered Aug 23 '18 at 15:53

3

5/(-3) = -1;
(-5)/3 = -1; 

If that is agreed then let's calculate the remainder

Remainder = Dividend - ( Divisor * Factor)

5 - (-3 * -1) = 2
-5 - (3 * -1) = -2

answered Aug 23 '18 at 15:53

Pushparaj

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The sign of the modulo operator result?

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