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Random Writer

Random Writer. Joe Zachary School of Computing University of Utah. Random Writer. Based on an idea by Claude Shannon (1948) popularized by A.K. Dewdney (1989) Generates random text based on the patterns in a source file Both fun and appropriate for CS 2 students

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Random Writer

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  1. Random Writer Joe Zachary School of Computing University of Utah

  2. Random Writer • Based on an idea by Claude Shannon (1948) popularized by A.K. Dewdney (1989) • Generates random text based on the patterns in a source file • Both fun and appropriate for CS 2 students • Uses file input/output, string manipulation, dynamic linear data structures, and random number generation

  3. King James Bible For every man putteth one and my mother: for them, to David sent Samson, and a sacrifice. Then went Samson down, and his father and his mother, to Timnath, and came to the vineyards of Timnath: and, behold, a young lion roared against him. Now the ark; and treasures upon them: and, Who also in the evil: so do your heart?

  4. King James Bible (Level 6) For every man putteth one and my mother: for them, to David sent Samson, and a sacrifice. Then went Samson down, and his father and his mother, to Timnath, and came to the vineyards of Timnath: and, behold, a young lion roared against him. Now the ark; and treasures upon them: and, Who also in the evil: so do your heart?

  5. Tom Sawyer Huck started to act very intelligently on the back of his pocket behind, as usual on Sundays. He was always dressed fitten for drinking some old empty hogsheads. The men contemplated the treasure awhile in blissful silence.

  6. Tom Sawyer (Level 8) Huck started to act very intelligently on the back of his pocket behind, as usual on Sundays. He was always dressed fitten for drinking some old empty hogsheads. The men contemplated the treasure awhile in blissful silence.

  7. Hamlet Ay me, what act, That roars so loud and thunders in the index? Worse that a rat? Dead for a ducat, drugs fit that I bid you not? Leave heart; for to our lord, it we show him, but skin and he, my lord, I have fat all not over thought, good my lord?

  8. Hamlet (Level 5) Ay me, what act, That roars so loud and thunders in the index? Worse that a rat? Dead for a ducat, drugs fit that I bid you not? Leave heart; for to our lord, it we show him, but skin and he, my lord, I have fat all not over thought, good my lord?

  9. C++ Programs int temp = A[0]; A[i-1] = A[j]; C[((A[j])>>(shift*8))& 0xff] + 1; node *m_pTop; m_pTop = pNext; while (p!=end) res = 0; int hash code = hash<string>()(key); float A = (sqrt(5)-1)/2; int index = floor(buckets * (hashcode * A - floor(hashcode * A)));

  10. C++ Programs (Level 7) int temp = A[0]; A[i-1] = A[j]; C[((A[j])>>(shift*8))& 0xff] + 1; node *m_pTop; m_pTop = pNext; while (p!=end) res = 0; int hash code = hash<string>()(key); float A = (sqrt(5)-1)/2; int index = floor(buckets * (hashcode * A - floor(hashcode * A)));

  11. Niftiness • Not a toy: it slurps up entire books • Defies expectations: it turns out to be both straightforward and educational • Entertaining: I run a contest to find the funniest generated text

  12. Level 0 The probability that c is the next character to be produced equals the probability that c occurs in the source file. rla bsht eS ststofo hhfosdsdewno oe wee h .mr ae irii ela iad o r te u t mnyto onmalysnce, ifu en c fDwn oee iteo

  13. Level 1 Let s be the previously produced character. The probability that c is the next character to be produced equals the probability that c follows s in the source text. "Shand tucthiney m?" le ollds mind Theybooure He, he s whit Pereg lenigabo Jodind alllld ashanthe ainofevids tre lin--p asto oun

  14. Level K Let seed be the previously produced k (4 in this case) characters. The probability that c is the next character to be produced equals the probability that c follows seed in the source text. Mr. Welshman, but him awoke, the balmy shore. I'll give him that he couple overy because in the slated snufflindeed structure's

  15. Algorithm • Pick a random k-letter seed from the text • Repeatedly: • Make a list of every character that follows the seed in the text • Randomly pick a character c from the text • Output c • Remove the first character from the seed and append c

  16. Example at Level 2 Seed: th Text: We hold these truths to be self-evident: that all men are created equal; that they List: [e, s, a, a, e] Character: s (20% of the time) New seed: hs

  17. http://nifty.stanford.edu/

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