Ultraviolet A 408-Uniform Generator

Uniform Generator

Computer simulations often require random numbers. One way to generate pseudo-random numbers is via a function of the form

Where ''" is the modulus operator.

Such a function will generate pseudo-random numbers (Seed) Between 0 and
MoD-1. One problem with functions of this form is that they will always generate the same pattern over and over. In order to minimize this effect, selecting
StepAndMoDValues carefully can result in a uniform distribution of all values between (and including) 0 and
MoD-1.

For example, ifStep= 3 andMoD= 5, the function will generate the series of pseudo-random numbers 0, 3, 1, 4, 2 in a repeating cycle. in this example, all of the numbers between and including 0 and
MoD-1 will be generated everyMoDIterations of the function. Note that by the nature of the function to generate the same
Seed(X+ 1) every timeSeed(X) Occurs means that if a function will generate all the numbers between 0 and
MoD-1, it will generate pseudo-random numbers uniformly with everyMoDIterations.

IfStep= 15 andMoD= 20, the function generates the series 0, 15, 10, 5 (or any other repeating series if the initial seed is other than 0). This is a poor selection
StepAndMoDBecause no initial seed will generate all of the numbers from 0 and
MoD-1.

Your program will determine if choicesStepAndMoDWill generate a uniform distribution of pseudo-random numbers.

Input

Each line of input will contain a pair of integersStepAndMoDIn that order (
).

Output

For each line of input, your program shocould printStepValue right-justified in columns 1 through 10,
MoDValue right-justified in columns 11 through 20 and either''Good choice"Or''Bad choice"Left-justified starting in column 25.''Good choice"Message shoshould be printed when the selection
StepAndMoDWill generate all the numbers between and including 0 and
MoD-1 when mod numbers are generated. Otherwise, your program shocould print the message''Bad choice". After each output test set, your program shocould print exactly one blank line.

Sample Input

3 515 2063923 99999

Sample output

         3         5    Good Choice        15        20    Bad Choice     63923     99999    Good Choice

#include <stdio.h>#include <string.h>long a[10000001],step,mod,num,x,i;void main(){  while (scanf("%d%d",&step,&mod)!=EOF) {for (i=0;i<mod;i++) a[i]=0;  num=0; x=step;  while (a[(x+step)%mod]==0)  {++num;   x=(x+step)%mod;   a[x]=1;  }  printf("%10d%10d    ",step,mod); if (num==mod) printf("Good Choice\n\n");          else printf("Bad Choice\n\n"); }}

At 10-20, MOD 25th outputs good or bad 21 22 23 24 four spaces into five-I will go