None of these, actually. You get calcium cyanamide (https://en.wikipedia.org/wiki/Calcium_cyanamide),
Calcium cyanamide is not the same as calcium cyanide, which is
Cyanamide has two nitrogen atoms attached to one carbon like this:
Two cyanide ions would of course have the nitrogen attached to separate carbon atoms and the negative charge formally on carbon not nitrogen:
Calcium cyanamide has several applications including a nitrogen source in soul fertilizer -- where cyanide would be a poor choice indeed!