get user input from main

src/primzahl/main.c

@@ -4,7 +4,9 @@
 #include <stdbool.h>
 
 int main() {
+    int minInput = 0;
 
+    int num = usergetd("Enter a positive number: ", minInput, NULL);
 
-	return 0;
+    return 0;
 }