finished random map generation

src/rng.cc

@@ -35,3 +35,7 @@ int RNG::get_curr_rand_num() const {
 bool RNG::trial(fraction &psuccess) {
         return (rand() % psuccess.denominator) < psuccess.numerator;
 }
+
+bool RNG::coin_flip() const {
+        return rand() % 2;
+}