Problem of the Day
A new programming or logic puzzle every Mon-Fri

This one should hopefully having you thinking outside of the box. Without using any of the built in random functions of your chosen programming language or OS, create a function that returns a random number. Feel free to statically define seed numbers if it helps.

Comments:

• David - 10 years, 5 months ago

  This generator is simple and has a variable repetition cycle based on the seed, but it has good pseudo-randomness for a small number of values. It was good enough for von Neumann. I modified his algorithm by adding use of current time.

  #include <time.h>
  
  unsigned short int simpleRand(short int k = 0) { //This allows for an optional user seed
   static unsigned long int c = 0;
   unsigned short int x;
   time_t d;
   time(&d);
   if(0 == c) {
       c = (short int) d; 
  }
   c = k;
   //This does nothing for k= 0 c *= c; x = c >> 4 & 0xffff;   return x;
   }
  

  This next function is a bit of being silly.

   int RandAll(int m) { 
  return 221; //Chosen before hand by fair arbitration //Guaranteed to be random
   }
  

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