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This message was edited by gaetano at 2004-5-5 4:6:11
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please can anyone give me the algorithms for finding prime numbers below a number, given that number.
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: The maybe easiest implementation for an algorithm which finds primes
: in a given range is the so-called "Sieve Of Erathostenes".
:
: The advantages:
: - you will find really every prime
: - every found prime is 100% a prime
:
: The disadvantages:
: - the array takes a lot of memory
: - the computation time is long for high ranges
:
: If you need the "sieve" in another language than C/C++, just use any
: search engine. You'll find everything you need ...
:
:
:
: #include <iostream>
: using namespace std;
:
: int
: main (void)
: {
: long max;
: bool *primes;
:
: cout << " Calculate prime numbers (sieve of Erathostenes)\n\n";
: cout << " Highest number to test: ";
: cin >> max;
:
: if (max < 2) {
: cerr << " Error: Invalid value!\n"
: << " Number must be greater than 2.\n";
: return 1;
: }
:
: // Create array and exclude 0 and 1
: primes = new bool[max + 1];
:
: // Fill list with all positive integers
: for (long i=0; i<=max; i++)
: primes[i] = true;
:
: // The testing ...
: for (long i=2; i<=max; i++)
: for (long j=2; i*j<max; j++)
: primes[i*j] = false;
:
: // The index of the array equals the numbers
: // If you want to look whether 7 is a prime, just try
: // if `(primes[7])'
:
: // Print them
: for (long i=2; i<=max; i++)
: if (primes[i])
: cout << i << endl;
:
: delete[] primes;
: return 0;
: }
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:
:
Can you give me some pseudocode to Intel assembly? thanks didn't find it on google
