projEuler10.ts

inputs/passing/projEuler10.ts

@@ -0,0 +1,99 @@
+export default function main() {
+  let sum = 0;
+  let gen = new PrimeGenerator();
+
+  while (true) {
+    const p = gen.next();
+
+    if (p >= 2000000) {
+      return sum;
+    }
+
+    sum += p;
+  }
+}
+
+class PrimeGenerator {
+  pcg: PrimeCandidatesGenerator;
+
+  constructor() {
+    this.pcg = new PrimeCandidatesGenerator();
+  }
+
+  next() {
+    while (true) {
+      const candidate = this.pcg.next();
+
+      if (isPrime(candidate)) {
+        return candidate;
+      }
+    }
+  }
+}
+
+function isPrime(n: number) {
+  let pcg = new PrimeCandidatesGenerator();
+
+  while (true) {
+    const pc = pcg.next();
+
+    if (pc * pc > n) {
+      return true;
+    }
+
+    if (n % pc === 0) {
+      return false;
+    }
+  }
+}
+
+class PrimeCandidatesGenerator {
+  gen: Gen235 | GenMod30;
+
+  constructor() {
+    this.gen = new Gen235();
+  }
+
+  next() {
+    let c = this.gen.next();
+
+    if (c !== undefined) {
+      return c;
+    }
+
+    this.gen = new GenMod30();
+    return this.gen.next();
+  }
+}
+
+class Gen235 {
+  nums: number[];
+  i: number;
+
+  constructor() {
+    this.nums = [2, 3, 5];
+    this.i = 0;
+  }
+
+  next() {
+    return this.nums[this.i++];
+  }
+}
+
+class GenMod30 {
+  nums: number[];
+  i: number;
+
+  constructor() {
+    this.nums = [1, 7, 11, 13, 17, 19, 23, 29];
+    this.i = 1;
+  }
+
+  next() {
+    const rem = this.i % 8
+    const rounds = (this.i - rem) / 8;
+    this.i++;
+
+    return 30 * rounds + this.nums[rem];
+  }
+}