1 files changed, 31 insertions, 0 deletions
diff --git a/random.c b/random.c
new file mode 100644
index 0000000..a0a19c7
--- /dev/null
+++ b/random.c
@@ -0,0 +1,31 @@
+/* concatenation of following two 16-bit multiply with carry generators */
+/* x(n)=a*x(n-1)+carry mod 2^16 and y(n)=b*y(n-1)+carry mod 2^16, */
+/* number and carry packed within the same 32 bit integer.        */
+/******************************************************************/
+
+unsigned int rand( void );           /* returns a random 32-bit integer */
+void  rand_seed( unsigned int, unsigned int );      /* seed the generator */
+
+/* return a random float >= 0 and < 1 */
+#define rand_float          ((double)rand() / 4294967296.0)
+
+static unsigned int SEED_X = 521288629;
+static unsigned int SEED_Y = 362436069;
+
+
+unsigned int rand ()
+   {
+   static unsigned int a = 18000, b = 30903;
+
+   SEED_X = a*(SEED_X&65535) + (SEED_X>>16);
+   SEED_Y = b*(SEED_Y&65535) + (SEED_Y>>16);
+
+   return ((SEED_X<<16) + (SEED_Y&65535));
+   }
+
+
+void rand_seed( unsigned int seed1, unsigned int seed2 )
+   {
+   if (seed1) SEED_X = seed1;   /* use default seeds if parameter is 0 */
+   if (seed2) SEED_Y = seed2;
+   }