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src/euler46/Cargo.toml

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+[package]
+name = "euler46"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+itertools = "0.14"
+primes = { version = "*", path = "../../lib/primes" }

src/euler46/src/main.rs

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+use primes::Primes;
+
+const MAX: usize = 1_000_000;
+
+fn main() {
+    let primes = Primes::get_between(2, MAX);
+    'outer: for number in iter_odd_composite_numbers(&primes) {
+        for prime in primes.iter().take_while(|p| **p < number) {
+            'inner: for n in 1_usize.. {
+                let sum = prime + 2 * n.pow(2);
+                if sum == number {
+                    continue 'outer;
+                }
+                if sum > number {
+                    break 'inner;
+                }
+            }
+        }
+        println!("{number}");
+        break 'outer;
+    }
+}
+
+fn iter_odd_composite_numbers(primes: &Primes<usize>) -> impl Iterator<Item = usize> {
+    (3..MAX).step_by(2).filter(|n| !primes.contains(n))
+}