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authorTyge Løvset <[email protected]>2023-03-01 14:36:38 +0100
committerTyge Løvset <[email protected]>2023-03-01 14:36:38 +0100
commit78a7e85535fd02e643bf98103223d4218e80133f (patch)
treebe22b46aaa7ac48b29125863d27db591cf12dcdf /misc/examples/prime.c
parent8fdcfbf621b5e8c1298a89579594db0817adce26 (diff)
downloadSTC-modified-78a7e85535fd02e643bf98103223d4218e80133f.tar.gz
STC-modified-78a7e85535fd02e643bf98103223d4218e80133f.zip
Moved algorithm examples to algo folder.
Diffstat (limited to 'misc/examples/prime.c')
-rw-r--r--misc/examples/prime.c53
1 files changed, 0 insertions, 53 deletions
diff --git a/misc/examples/prime.c b/misc/examples/prime.c
deleted file mode 100644
index e705dcb7..00000000
--- a/misc/examples/prime.c
+++ /dev/null
@@ -1,53 +0,0 @@
-#include <stdio.h>
-#include <math.h>
-#include <time.h>
-#include <stc/cbits.h>
-#include <stc/algo/filter.h>
-#include <stc/algo/crange.h>
-
-
-cbits sieveOfEratosthenes(int64_t n)
-{
- cbits bits = cbits_with_size(n/2 + 1, true);
- int64_t q = (int64_t)sqrt((double) n) + 1;
- for (int64_t i = 3; i < q; i += 2) {
- int64_t j = i;
- for (; j < n; j += 2) {
- if (cbits_test(&bits, j>>1)) {
- i = j;
- break;
- }
- }
- for (int64_t j = i*i; j < n; j += i*2)
- cbits_reset(&bits, j>>1);
- }
- return bits;
-}
-
-int main(void)
-{
- int64_t n = 1000000000;
- printf("Computing prime numbers up to %" c_ZI "\n", n);
-
- clock_t t1 = clock();
- c_with (cbits primes = sieveOfEratosthenes(n + 1), cbits_drop(&primes)) {
- int64_t np = cbits_count(&primes);
- clock_t t2 = clock();
-
- printf("Number of primes: %" c_ZI ", time: %f\n\n", np, (float)(t2 - t1) / (float)CLOCKS_PER_SEC);
- puts("Show all the primes in the range [2, 1000):");
- printf("2");
- c_forrange (i, 3, 1000, 2)
- if (cbits_test(&primes, i>>1)) printf(" %lld", i);
- puts("\n");
-
- puts("Show the last 50 primes using a temporary crange generator:");
- crange R = crange_make(n - 1, 0, -2);
- c_forfilter (i, crange, R
- , cbits_test(&primes, *i.ref>>1)
- , c_flt_take(i, 50)) {
- printf("%lld ", *i.ref);
- if (c_flt_last(i) % 10 == 0) puts("");
- }
- }
-}