Hey guys, just looking for an explanation for the following algorithm. It is in my textbook, and there isn't really an explanation. I don't really see how the algorithm works, but I will add what I do know, and hopefully one of you can help. Thanks.(adsbygoogle = window.adsbygoogle || []).push({});

Furthermore, I am not entirely sure why count was initialized at the beginning of the algorithm, I never saw it used.PHP:

//this initial declarations produces an array with N elements.

int N = 40;

bool table[N];

int count = 0;

//this while loop assigns every element in the array to true.

int i = 0;

while (i < N)

{

table[i]=true;

i=i+1;

}

//from here is where I get lost.

table[0]=false; //assigns false value to the first element in the array.

i=2; //starts the next loop at 2.

while (i < N)

{

if (table[i]

{

cout << i << " is prime." << endl;

int j = 2*i;

while (j < N)

{

table[j]=false;

j=j+i;

}

}

i=i+1;

}

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# Boolean array to identify prime numbers - C++

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