2 files changed, 142 insertions, 1 deletions
diff --git a/wk5/lect/insert.c b/wk5/lect/insert.c
index de94253..5d1854b 100644
--- a/wk5/lect/insert.c
+++ b/wk5/lect/insert.c
@@ -1,10 +1,10 @@
 #include <cs50.h>
 #include <ctype.h>
+#include <math.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <math.h>
 
 typedef struct node
 {
diff --git a/wk5/pset/inheritance/inheritance.c b/wk5/pset/inheritance/inheritance.c
new file mode 100644
index 0000000..0f3fd13
--- /dev/null
+++ b/wk5/pset/inheritance/inheritance.c
@@ -0,0 +1,141 @@
+// Simulate genetic inheritance of blood type
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <math.h>
+
+// Each person has two parents and two alleles
+typedef struct person
+{
+    struct person *parents[2];
+    char alleles[2];
+} person;
+
+const int GENERATIONS = 3;
+const int INDENT_LENGTH = 4;
+
+person *create_family(int generations);
+void print_family(person *p, int generation);
+void free_family(person *p);
+char random_allele();
+
+int main(void)
+{
+    // Seed random number generator
+    srand(time(0));
+
+    // Create a new family with three generations
+    person *p = create_family(GENERATIONS);
+
+    // Print family tree of blood types
+    print_family(p, 0);
+
+    // Free memory
+    free_family(p);
+}
+
+// Create a new individual with `generations`
+person *create_family(int generations)
+{
+    // TODO: Allocate memory for new person
+    person *new = malloc(sizeof(person));
+
+    // If there are still generations left to create
+    if (generations > 1)
+    {
+        // Create two new parents for current person by recursively calling create_family
+        person *parent0 = create_family(generations - 1);
+        person *parent1 = create_family(generations - 1);
+
+        // TODO: Set parent pointers for current person
+        new->parents[0] = *parent0;
+        new->parents[1] = *parent1;
+
+        // TODO: Randomly assign current person's alleles based on the alleles of their parents
+        new->alleles[0] = new->parents[0]->alleles[round(random() / ((double) RAND_MAX + 1))];
+        new->alleles[1] = new->parents[1]->alleles[round(random() / ((double) RAND_MAX + 1))];
+    }
+
+    // If there are no generations left to create
+    else
+    {
+        // TODO: Set parent pointers to NULL
+        new->parents[0] = NULL;
+        new->parents[1] = NULL;
+
+        // TODO: Randomly assign alleles
+        // new->alleles[0] = round(random() / ((double) RAND_MAX + 1));
+        // new->alleles[1] = round(random() / ((double) RAND_MAX + 1));
+    }
+
+    // TODO: Return newly created person
+    return NULL;
+}
+
+// Free `p` and all ancestors of `p`.
+void free_family(person *p)
+{
+    // TODO: Handle base case
+
+    // TODO: Free parents recursively
+
+    // TODO: Free child
+}
+
+// Print each family member and their alleles.
+void print_family(person *p, int generation)
+{
+    // Handle base case
+    if (p == NULL)
+    {
+        return;
+    }
+
+    // Print indentation
+    for (int i = 0; i < generation * INDENT_LENGTH; i++)
+    {
+        printf(" ");
+    }
+
+    // Print person
+    if (generation == 0)
+    {
+        printf("Child (Generation %i): blood type %c%c\n", generation, p->alleles[0], p->alleles[1]);
+    }
+    else if (generation == 1)
+    {
+        printf("Parent (Generation %i): blood type %c%c\n", generation, p->alleles[0], p->alleles[1]);
+    }
+    else
+    {
+        for (int i = 0; i < generation - 2; i++)
+        {
+            printf("Great-");
+        }
+        printf("Grandparent (Generation %i): blood type %c%c\n", generation, p->alleles[0], p->alleles[1]);
+    }
+
+    // Print parents of current generation
+    print_family(p->parents[0], generation + 1);
+    print_family(p->parents[1], generation + 1);
+}
+
+// Randomly chooses a blood type allele.
+char random_allele()
+{
+    int r = rand() % 3;
+    if (r == 0)
+    {
+        return 'A';
+    }
+    else if (r == 1)
+    {
+        return 'B';
+    }
+    else
+    {
+        return 'O';
+    }
+}