Set mutation chance super low and check for end case in mutation

src/base.h

@@ -39,8 +39,8 @@ typedef double f64;
 #define NUM_PROGRAMS_POW_2   8
 #define NUM_PROGRAMS         (1 << NUM_PROGRAMS_POW_2)
 
-#define MUTATION_CHANCE 0
-#define MUTATION_OFFSET 2
+#define MUTATION_CHANCE 10000
+#define MUTATION_OFFSET 3
 
 #endif
 

src/simulation.c

@@ -29,7 +29,7 @@ void simulation_iterate(simulation_t *sim)
 #if MUTATION_CHANCE
   for (u64 i = 0; i < SIMULATION_SIZE; ++i)
   {
-    if ((rand() % MUTATION_CHANCE) == 0)
+    if ((rand() % MUTATION_CHANCE) == (MUTATION_CHANCE - 1))
     {
       sim->memory[i] += (rand() % MUTATION_OFFSET) - (MUTATION_OFFSET / 2);
     }