uint64_t PrimeSieve::nthPrime(int64_t n, uint64_t start)
{
setStart(start);
double t1 = getWallTime();
if (n == 0)
n = 1; // Like Mathematica
else if (n > 0)
start = add_overflow_safe(start, 1);
else if (n < 0)
start = sub_underflow_safe(start, 1);
uint64_t stop = start;
uint64_t dist = nthPrimeDist(n, 0, start);
uint64_t nthPrimeGuess = add_overflow_safe(start, dist);
int64_t count = 0;
int64_t tinyN = 10000;
tinyN = max(tinyN, pix(isqrt(nthPrimeGuess)));
while ((n - count) > tinyN ||
sieveBackwards(n, count, stop))
{
if (count < n)
{
checkLimit(start);
dist = nthPrimeDist(n, count, start);
stop = add_overflow_safe(start, dist);
count += countPrimes(start, stop);
start = add_overflow_safe(stop, 1);
}
if (sieveBackwards(n, count, stop))
{
checkLowerLimit(stop);
dist = nthPrimeDist(n, count, stop);
start = sub_underflow_safe(start, dist);
count -= countPrimes(start, stop);
stop = sub_underflow_safe(start, 1);
}
}
if (n < 0)
count -= 1;
checkLimit(start);
uint64_t overValue = 3;
dist = nthPrimeDist(n, count, start) * overValue;
stop = add_overflow_safe(start, dist);
NthPrime np;
np.findNthPrime(n - count, start, stop);
seconds_ = getWallTime() - t1;
return np.getNthPrime();
}
countPrimes(int a, int b)
{
if(a>b)
return 0;
if(isprime(b))
{
printf("%d ",b);
return 1 + countPrimes(a,b-1);
}
else
return countPrimes(a,b-1);
}
int main(int argc, char const *argv[])
{
int i;
int N = atoi(argv[1]);
int nodesAlloc = ((N-2)/16384) + 2;
head= ( seg * ) malloc(sizeof(seg));
pt=head;
for (i=1;i<nodesAlloc;i++) {
pt->next = ( seg *) malloc(sizeof (seg)); //allocate forward nodes
pt->prev = pt; //allocate backward nodes
pt=pt->next;
}
printf("Allocated %d nodes\n",i);
sieveOfE(N);
primecount = countPrimes(N)-1;
printf("Amount of primes = %d \n", primecount);
while(numbers != EOF){
printf("Enter your numbers or EOF:");
// if an odd integer is entered or eof is detected exit
if ( scanf("%d", &numbers) == EOF || numbers % 2 != 0 )
{
break;
}
else{goldbach(numbers);}
}
return 0;
}
int main(void)
{
int max_number;
float ticks;
char * PrimeNumbers;
printf("\nMaximum number: ");
scanf("%u",&max_number);
PrimeNumbers = (char *) calloc(max_number % 16 == 0 ? max_number / 16 : 1 + max_number / 16, 1);
if (!PrimeNumbers)
{
fprintf(stderr, "Unable to allocate memory\n");
return -1;
}
ticks = clock();
findPrimes(PrimeNumbers, max_number);
//printf("2\n");printPrimes(PrimeNumbers, max_number);
printf("Found %u primes between 2 and %u in %g seconds\n",countPrimes(PrimeNumbers, max_number),max_number,(clock() - ticks)/CLOCKS_PER_SEC);
free(PrimeNumbers);
return 0;
}
main()
{
int a,b;
printf("Enter values of a and b :");
scanf("%d %d",&a,&b);
printf("\nTotal prime numbers = %d\n",countPrimes(a,b));
}
int main(void) {
long long n;
readInputData(&n);
writeOutputData(countPrimes(n), n);
return 0;
}
int main()
{
double start = GetTickCount();
countPrimes(150000);
double end = GetTickCount();
printf("\ncost=%lfms\n", end - start);
return 0;
}
int main(int argc, char const *argv[])
{
int N;
N = 100;
printf("%d\n", countPrimes(N));
return 0;
}
int main(int argc, char *argv[])
{
if (argc != 2) {
fprintf(stderr, "Usage: %s n\n", argv[0]);
return 1;
}
printf("%d\n", countPrimes(atoi(argv[1])) );
return 0;
}
int main()
{
int n=0;
while(1)
{
scanf("%i",&n);
printf("%i\n", countPrimes(n));
}
return 1;
}
//个人测试用例
int main(void)
{
int num;
scanf("%d", &num);
int cnt = countPrimes(num);
printf("\n%d\n", cnt);
return 0;
}
void readLinesFromFile(const char* filePath) {
assert(filePath);
std::string lineBuffer;
std::ifstream file;
file.open(filePath);
std::vector<std::vector<int> > primeRanges;
while (std::getline(file, lineBuffer)) {
if (lineBuffer.empty()) { continue; }
std::vector<int> range = intenizeString(lineBuffer, ",");
primeRanges.push_back(range);
}
countPrimes(primeRanges);
}
int main() {
int e, d, c = 0;
for(int a = -999; a <= 999; ++a) {
for(int b = -999; b <= 999; ++b) {
int k = countPrimes(a,b);
if(k > c) {
c = k;
e = a;
d = b;
}
}
}
std::cout << e*d;
}
void sieve(int n) {
int i, p = 2, pmax = (int)sqrt(n);
char set[n];
unsigned long count = sizeof(set) / sizeof(set[0]);
for (i = 0; i < count; i++) { set[i] = 1; }
set[0] = set[1] = 0;
while (p <= pmax) {
for (i = p * p; i < count; i += p) { set[i] = 0; }
do { p++; } while (!set[p]); // continue search for primes
};
countPrimes(set, count);
}
int main() {
int n;
scanf("%d", &n);
printf("%d ", countPrimes(n));
return 0;
}
int main() {
/* 348513 */
printf("%d\n", countPrimes(5000000));
return 0;
}
int main()
{
printf_s("The result is: %d\n", countPrimes(121));
return 0;
}
int main()
{
int ret = countPrimes(1500000);
printf("%d\n", ret);
}
int main()
{
int count = countPrimes(1500000);
printf("%d\n", count);
return 0;
}
