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+\ Fast Random Number Generator algorithm by George Marsaglia "Xorshift RNGs"
+
+-rnd
+marker -rnd
+
+: xorshift ( n -- n )
+ dup #13 lshift xor
+ dup #17 rshift xor
+ dup #5 lshift xor
+;
+
+variable (rnd) \ seed
+ticks (rnd) ! \ initialize seed
+
+: rnd ( -- n )
+ (rnd) @ xorshift dup (rnd) !
+;