init

problems/p37/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "p37"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+primal = { workspace = true }

problems/p37/src/main.rs

@@ -0,0 +1,68 @@
+use primal::{self, Primes, is_prime};
+
+fn is_truncatable_primes(n: u32) -> bool {
+    match n {
+        2 => false,
+        3 => false,
+        5 => false,
+        7 => false,
+        _ => is_right_truncatable_primes(n) && is_left_truncatable_primes(n),
+    }
+}
+#[test]
+fn test_is_truncatable_primes() {
+    assert!(is_truncatable_primes(3797));
+}
+fn is_left_truncatable_primes(n: u32) -> bool {
+    let mut n = n;
+    while n > 0 {
+        if is_prime(n as u64) {
+            n /= 10;
+        } else {
+            return false;
+        }
+    }
+    true
+}
+#[test]
+fn test_is_left_truncatable_primes() {
+    assert!(is_left_truncatable_primes(3797));
+}
+
+fn is_right_truncatable_primes(n: u32) -> bool {
+    let mut n = n;
+    while n > 0 {
+        if is_prime(n as u64) {
+            let string = &n.to_string()[1..];
+
+            n = match string.len() {
+                0 => {
+                    return true;
+                }
+                _ => string.parse().unwrap(),
+            }
+        } else {
+            return false;
+        }
+    }
+    true
+}
+#[test]
+fn test_is_right_truncatable_primes() {
+    assert!(is_right_truncatable_primes(3797));
+}
+
+fn main() {
+    let mut p_vec = Vec::new();
+    for prime in Primes::all() {
+        if is_truncatable_primes(prime as u32) {
+            p_vec.push(prime as u32);
+        }
+        if p_vec.len() == 11 {
+            break;
+        }
+    }
+    let sum = p_vec.iter().sum::<u32>();
+    dbg!(p_vec);
+    println!("sum: {sum}");
+}