print the ggT of those two numbers

src/ggT/main.c

@@ -7,6 +7,7 @@ int main(){
     int firstNum = usergetd("first number: ", 0, NULL);
     int secondNum = usergetd("second number: ", 0, NULL);
     int result = ggT(firstNum, secondNum);
+    printf("The ggT is: %d\n", result);
 
     return 0;
 }