sieve

sieve_openmp.c

@@ -0,0 +1,44 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <omp.h>
+
+void print_primes(char *nums_array, long max_prime)
+{
+	int i;
+	for(i = 2; i <= max_prime; i++)
+	{
+		if(nums_array[i] == 0)
+		{
+			printf("%d\n", i);
+		}
+	}
+}
+
+int main(int argc, char** argv)
+{
+	if (argc < 2)
+	{
+		printf("missing arg");
+		return 1;
+	}
+	long max_prime = atoi(argv[1]);
+	char *nums_array = (char *) calloc(max_prime + 1, sizeof(char));
+
+	long i;
+	for(i = 2; i <= max_prime; i++)
+	{
+		if (nums_array[i] == 0)
+		{
+			long j;
+			#pragma omp parallel for schedule(static)
+			for(j = i*i; j <= max_prime; j += i)
+			{
+//				printf("%d\n", omp_get_thread_num());
+				nums_array[j] = 1;
+			}
+		}
+	}
+
+//	print_primes(nums_array, max_prime);
+	return 0;
+}