implemented case if at least one input is zero

src/kgV/kgV.c

@@ -2,5 +2,6 @@
 #include "ggT.h"
 
 int kgV(int a, int b){
+    if(a == 0 || b == 0) return 0;
     return a*b/ ggT(a, b);
 }