division: added integer division (because i can't figure out how to do it better

README.md

@@ -22,6 +22,7 @@ double silly_to_double(silly); // convert a silly number into a double
 silly silly_add(silly, silly); // addition
 silly silly_sub(silly, silly); // subtraction
 silly silly_mul(silly, silly); // multiplication
+silly silly_div(silly, silly); // division (integer precision only :( )
 
 char* silly_to_string(silly); // converts a fixed point value to a string (memory is now yours)
 ```

silly.c

@@ -77,6 +77,18 @@ silly silly_mul(silly x, silly y) {
   return z;
 }
 
+silly silly_div(silly x, silly y) {
+  silly z;
+  z.sign = x.sign ^ y.sign;
+
+  uint64_t x0 = (((uint64_t) x.before) << 32) + x.after;
+  uint64_t y0 = (((uint64_t) y.before) << 32) + y.after;
+  z.before = x0 / y0;
+  z.after = 0;
+
+  return z;
+}
+
 char* silly_to_string(silly s) {
   char* res = malloc(23);
 

silly.h

@@ -15,6 +15,7 @@ silly make_silly(short, int, int);
 silly silly_add(silly, silly);
 silly silly_sub(silly, silly);
 silly silly_mul(silly, silly);
+silly silly_div(silly, silly);
 
 silly silly_from_float(float);
 silly silly_from_double(double);

tests/test.c

@@ -116,12 +116,31 @@ TEST silly_conversion() {
   PASS();
 }
 
+TEST silly_division() {
+  silly x = make_silly(0, 10, 0);
+  silly y = make_silly(1, 5, 0);
+
+  ASSERT_EQ_FMT(-2.0, silly_to_double(silly_div(x, y)), "%f");
+
+  y = make_silly(1, 2, 5);
+
+  ASSERT_EQ_FMT(-4.0, silly_to_double(silly_div(x, y)), "%f");
+
+  // :(
+  y = make_silly(1, 2, 3);
+
+  ASSERT_EQ_FMT(-4.0, silly_to_double(silly_div(x, y)), "%f");
+
+  PASS();
+}
+
 SUITE(tests) {
     RUN_TEST(silly_zeros_is_zero);
     RUN_TEST(silly_string);
     RUN_TEST(silly_addition);
     RUN_TEST(silly_subtraction);
     RUN_TEST(silly_multiplication);
+    RUN_TEST(silly_division);
     RUN_TEST(silly_conversion);
 }