Style changes to primes
This commit is contained in:
parent
373792c113
commit
72811cbcd3
20
primes.c
20
primes.c
|
@ -8,7 +8,7 @@
|
||||||
* runs in O(sqrt(n))
|
* runs in O(sqrt(n))
|
||||||
*
|
*
|
||||||
*/
|
*/
|
||||||
bool isPrime (long n) {
|
bool isPrime(long n) {
|
||||||
if (n == 0 || n == 1)
|
if (n == 0 || n == 1)
|
||||||
return false;
|
return false;
|
||||||
|
|
||||||
|
@ -26,7 +26,7 @@ bool isPrime (long n) {
|
||||||
* runs in O(sqrt(n)/ln(n))
|
* runs in O(sqrt(n)/ln(n))
|
||||||
*
|
*
|
||||||
*/
|
*/
|
||||||
bool isPrimeMem (long n, long* primes) {
|
bool isPrimeMem(long n, long* primes) {
|
||||||
if (n == 0 || n == 1)
|
if (n == 0 || n == 1)
|
||||||
return false;
|
return false;
|
||||||
if (n == 2 || n == 3)
|
if (n == 2 || n == 3)
|
||||||
|
@ -50,15 +50,15 @@ bool isPrimeMem (long n, long* primes) {
|
||||||
* where the 0-based ith element is true if i is prime
|
* where the 0-based ith element is true if i is prime
|
||||||
* returns: number of primes in *primes_ptr
|
* returns: number of primes in *primes_ptr
|
||||||
*
|
*
|
||||||
* N.B. numOfPrimesUpper is an upper-bound of
|
* N.B. numOfPrimesUpper is an upper-bound of
|
||||||
* the prime-counting function, given by
|
* the prime-counting function, given by
|
||||||
* n/ln(n) * 1.25506
|
* n/ln(n) * 1.25506
|
||||||
*
|
*
|
||||||
* runs in O(n * sqrt(n)/ln(n)) (not a tight bound)
|
* runs in O(n * sqrt(n)/ln(n)) (not a tight bound)
|
||||||
*
|
*
|
||||||
*/
|
*/
|
||||||
|
|
||||||
long listOfPrimes (long n, long** primes_ptr, bool** primesTable_ptr) {
|
long listOfPrimes(long n, long** primes_ptr, bool** primesTable_ptr) {
|
||||||
*primesTable_ptr = calloc (n + 1, sizeof (bool));
|
*primesTable_ptr = calloc (n + 1, sizeof (bool));
|
||||||
|
|
||||||
if (n == 0 || n == 1) {
|
if (n == 0 || n == 1) {
|
||||||
|
@ -66,23 +66,23 @@ long listOfPrimes (long n, long** primes_ptr, bool** primesTable_ptr) {
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
|
||||||
long numOfPrimesUpper = (long) (n/log(n) * 1.25506);
|
long numOfPrimesUpper = (long) (n/log(n) * 1.25506);
|
||||||
*primes_ptr = malloc (sizeof (long) * numOfPrimesUpper);
|
*primes_ptr = malloc (sizeof (long) * numOfPrimesUpper);
|
||||||
long numOfPrimes = 0;
|
long numOfPrimes = 0;
|
||||||
for (long i = 0; i <= n; i++) {
|
for (long i = 0; i <= n; i++) {
|
||||||
if (isPrimeMem (i, *primes_ptr)) {
|
if (isPrimeMem(i, *primes_ptr)) {
|
||||||
(*primes_ptr)[numOfPrimes] = i;
|
(*primes_ptr)[numOfPrimes] = i;
|
||||||
(*primesTable_ptr)[i] = true;
|
(*primesTable_ptr)[i] = true;
|
||||||
numOfPrimes++;
|
numOfPrimes++;
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
if (numOfPrimes < numOfPrimesUpper) {
|
if (numOfPrimes < numOfPrimesUpper) {
|
||||||
long* tmp = realloc (*primes_ptr,
|
long* tmp = realloc (*primes_ptr,
|
||||||
sizeof (long) * numOfPrimes);
|
sizeof (long) * numOfPrimes);
|
||||||
if (tmp != NULL)
|
if (tmp != NULL)
|
||||||
*primes_ptr = tmp;
|
*primes_ptr = tmp;
|
||||||
}
|
}
|
||||||
|
|
||||||
return numOfPrimes;
|
return numOfPrimes;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
@ -92,7 +92,7 @@ long listOfPrimes (long n, long** primes_ptr, bool** primesTable_ptr) {
|
||||||
* runs in O(n ln(ln(n))) apparently
|
* runs in O(n ln(ln(n))) apparently
|
||||||
*
|
*
|
||||||
*/
|
*/
|
||||||
void sieveOfEratosthenes (int n, bool** primesTable_ptr) {
|
void sieveOfEratosthenes(int n, bool** primesTable_ptr) {
|
||||||
*primesTable_ptr = malloc (sizeof (bool) * (n + 1));
|
*primesTable_ptr = malloc (sizeof (bool) * (n + 1));
|
||||||
for (int i = 0; i <= n; i++)
|
for (int i = 0; i <= n; i++)
|
||||||
(*primesTable_ptr)[i] = true;
|
(*primesTable_ptr)[i] = true;
|
||||||
|
|
10
primes.h
10
primes.h
|
@ -1,4 +1,6 @@
|
||||||
bool isPrime (long n);
|
#include <stdbool.h>
|
||||||
bool isPrimeMem (long n, long* primes);
|
|
||||||
long listOfPrimes (long n, long** primes_ptr, bool** primesTable_ptr);
|
bool isPrime(long n);
|
||||||
void sieveOfEratosthenes (int n, bool** primesTable_ptr);
|
bool isPrimeMem(long n, long* primes);
|
||||||
|
long listOfPrimes(long n, long** primes_ptr, bool** primesTable_ptr);
|
||||||
|
void sieveOfEratosthenes(int n, bool** primesTable_ptr);
|
||||||
|
|
Loading…
Reference in New Issue