Linear congruential generator: Difference between revisions

=={{header|dc}}==

''dc'' has no bitwise operations, so this program uses the modulus operator (<code>2147483648 %</code>) and division (<code>65536 /</code>). Fortunately, ''dc'' numbers cannot overflow to negative, so the modulus calculation involves only non-negative integers.

For BSD rand(): <lang dc>[*

* lrx -- (random number from 0 to 2147483647)

*

* Returns a number from the BSD rand() sequence.

* Seeded by storing a seed in register R.

*]sz

[lR 1103515245 * 12345 + 2147483648 % d sR]sr

[* Set seed to 1, then print the first 3 random numbers. *]sz

1 sR

lrx psz lrx psz lrx psz</lang>

<pre>1103527590

377401575

662824084</pre>

For Microsoft rand(): <lang dc>[*

* lrx -- (random number from 0 to 32767)

*

* Returns a number from the Microsoft rand() sequence.

* Seeded by storing a seed in register R.

*]sz

[lR 214013 * 2531011 + 2147483648 % d sR 65536 /]sr

[* Set seed to 1, then print the first 3 random numbers. *]sz

1 sR

lrx psz lrx psz lrx psz</lang>

<pre>41

18467

6334</pre>