jacob/cs3
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Well some things kinda work I guess.

Browse Source
This commit is contained in:
Jacob Signorovitch
2025-02-18 09:35:29 -05:00
parent 67683a7ef9
commit 6ef71e851c
1 changed files with 25 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

36
arrays/src/arrays/Main.java
View File

@@ -7,7 +7,7 @@ import tester.Tester;
class Sieve implements Iterator<Integer> { class Sieve implements Iterator<Integer> {
int cur; // The current number. int cur; // The current number.
int lim; // The largest number to check. int lim; // The largest number to check.
boolean[] isntPrime; // Where true, not a prime. boolean[] isntPrime; // One boolean for each number 0 to lim.
Sieve(int lim) { Sieve(int lim) {
if (lim < 2) if (lim < 2)
@@ -19,7 +19,24 @@ class Sieve implements Iterator<Integer> {
this.lim = lim; this.lim = lim;
this.isntPrime = new boolean[lim + 1]; this.isntPrime = new boolean[lim + 1];
this.isntPrime[3] = true; this.isntPrime[4] = true;
this.isntPrime[6] = true;
this.isntPrime[8] = true;
this.isntPrime[9] = true;
this.isntPrime[10] = true;
this.isntPrime[12] = true;
this.isntPrime[14] = true;
this.isntPrime[15] = true;
this.isntPrime[16] = true;
this.isntPrime[18] = true;
this.isntPrime[20] = true;
this.isntPrime[21] = true;
this.isntPrime[22] = true;
this.isntPrime[24] = true;
this.isntPrime[25] = true;
this.isntPrime[26] = true;
this.isntPrime[27] = true;
this.isntPrime[28] = true;
/* /*
for (int i = this.cur; i <= this.lim; i += this.cur) { for (int i = this.cur; i <= this.lim; i += this.cur) {
@@ -30,23 +47,20 @@ class Sieve implements Iterator<Integer> {
*/ */
} }
// [ false false false false false false false ] // [ false false true true false true false true ]
// [ 1 2 3 4 5 6 7 ] // [ 0 1 2 3 4 5 6 7 ]
//
// [ false false false false false false false ]
// [ 1 2 3 4 5 6 7 ]
public boolean hasNext() { return true; } public boolean hasNext() { return this.cur < this.lim; }
public Integer next() { public Integer next() {
while (this.isntPrime[this.cur]) this.cur++; while (this.isntPrime[this.cur]) this.cur++;
return this.cur; return this.cur++;
} }
} }
class Examples { class Examples {
void testSieve(Tester t) { void testSieve(Tester t) {
Sieve sieve = new Sieve(10); Sieve sieve = new Sieve(29);
t.checkExpect(sieve.hasNext(), true); t.checkExpect(sieve.hasNext(), true);
t.checkExpect(sieve.next(), 2); t.checkExpect(sieve.next(), 2);
t.checkExpect(sieve.next(), 3); t.checkExpect(sieve.next(), 3);
@@ -58,6 +72,6 @@ class Examples {
t.checkExpect(sieve.next(), 19); t.checkExpect(sieve.next(), 19);
t.checkExpect(sieve.next(), 23); t.checkExpect(sieve.next(), 23);
t.checkExpect(sieve.next(), 29); t.checkExpect(sieve.next(), 29);
t.checkExpect(sieve.next(), false); t.checkExpect(sieve.hasNext(), false);
} }
} }