PE 088 in progress, hard problem

projecteuler/088/src/main.rs

@@ -0,0 +1,53 @@
+use std::time::Instant;
+
+fn product(v: &Vec<u32>) -> u32 {
+    v.iter().fold(1, |acc, &v_x| acc * v_x)
+}
+
+fn naive_solution(k: u32) -> u32 {
+    todo!()
+}
+
+// ChatGPT failing once again
+fn chatgpt_solution(k: u32) -> u32 {
+    let mut prod = vec![2 * k; k as usize + 1];
+    let mut sums = vec![2 * k; k as usize + 1];
+
+    prod[1] = 1; // product of a single number is 1
+    sums[1] = 1; // sum of a single number is 1
+
+    // iterate through all possible combinations of numbers
+    for i in 2..k + 1 {
+        for j in (i..2 * k + 1).rev() {
+            for p in 1..=j - i {
+                let q = j - i - p;
+                if q >= i && prod[p as usize] <= j / prod[q as usize] {
+                    let s = sums[p as usize] + q;
+                    if s < sums[j as usize] {
+                        sums[j as usize] = s;
+                        prod[j as usize] = prod[p as usize] * q;
+                    }
+                }
+            }
+        }
+    }
+
+    sums[k as usize]
+}
+
+fn main() {
+    println!("Hello, this is Patrick!");
+    let now = Instant::now();
+
+    let max_k = 12;
+
+    let solution = naive_solution;
+    let result: u32 = (2..=max_k).into_iter().map(|k| solution(k)).sum();
+
+    println!(
+        "The sum of all minimal product-sum numbers for 2 <= k <= {} is: {}",
+        max_k, result,
+    );
+
+    println!("Time passed: {:?}", Instant::now() - now);
+}