From fb41ac47f10163bca06cb545f8aa9f1ab674b323 Mon Sep 17 00:00:00 2001
From: Philippe Zwietering <philippe.zwietering@gmail.com>
Date: Mon, 28 Oct 2024 13:41:26 +0100
Subject: [PATCH] =?UTF-8?q?=C3=8Berste=20poging=20projecteuler=2090?=
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---
 projecteuler/090/Cargo.lock  | 18 +++++++++++
 projecteuler/090/Cargo.toml  |  1 +
 projecteuler/090/src/main.rs | 62 ++++++++++++++++++++++++++++++++++--
 3 files changed, 79 insertions(+), 2 deletions(-)

diff --git a/projecteuler/090/Cargo.lock b/projecteuler/090/Cargo.lock
index 88ffcd8..7b9c150 100644
--- a/projecteuler/090/Cargo.lock
+++ b/projecteuler/090/Cargo.lock
@@ -2,6 +2,24 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "either"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "11157ac094ffbdde99aa67b23417ebdd801842852b500e395a45a9c0aac03e4a"
+
+[[package]]
+name = "itertools"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba291022dbbd398a455acf126c1e341954079855bc60dfdda641363bd6922569"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "main"
 version = "0.1.0"
+dependencies = [
+ "itertools",
+]
diff --git a/projecteuler/090/Cargo.toml b/projecteuler/090/Cargo.toml
index fca4e93..222e4c3 100644
--- a/projecteuler/090/Cargo.toml
+++ b/projecteuler/090/Cargo.toml
@@ -6,3 +6,4 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+itertools = "0.12.1"
diff --git a/projecteuler/090/src/main.rs b/projecteuler/090/src/main.rs
index 1d837a3..978462c 100644
--- a/projecteuler/090/src/main.rs
+++ b/projecteuler/090/src/main.rs
@@ -1,10 +1,68 @@
+use itertools::Itertools;
 use std::time::Instant;
 
+fn generate_cubes() -> Vec<Vec<u32>> {
+    (0..=9).combinations(6).collect()
+}
+
+fn is_valid_dice_configuration(d1: &Vec<u32>, d2: &Vec<u32>) -> bool {
+    let necessary_matches: Vec<_> = [
+        (0, 1),
+        (0, 4),
+        (0, 9),
+        (1, 6),
+        (2, 5),
+        (3, 6),
+        (4, 9),
+        (6, 4),
+        (8, 1),
+    ]
+    .into_iter()
+    .collect();
+
+    for (m1, m2) in necessary_matches {
+        if !(d1.contains(&m1) && d2.contains(&m2) || d1.contains(&m2) && d2.contains(&m1)) {
+            if m1 == 6 {
+                if !(d1.contains(&9) && d2.contains(&m2) || d1.contains(&m2) && d2.contains(&9)) {
+                    return false;
+                }
+            } else if m2 == 6 {
+                if !(d1.contains(&m1) && d2.contains(&9) || d1.contains(&9) && d2.contains(&m2)) {
+                    return false;
+                }
+            } else if m2 == 9 {
+                if !(d1.contains(&m1) && d2.contains(&6) || d1.contains(&6) && d2.contains(&m2)) {
+                    return false;
+                }
+            } else {
+                return false;
+            }
+        }
+    }
+
+    true
+}
+
 fn main() {
     println!("Hello, this is Patrick!");
     let now = Instant::now();
-    // We can't just loop through all possibilities because that would something in the order of
-    // (10*9*8*7*6*5)^2, which is a really big scary number
+
+    let dice1 = generate_cubes();
+    let dice2 = generate_cubes();
+
+    assert_eq!(dice1.len(), 210);
+
+    let mut result = 0;
+
+    for d1 in dice1.iter() {
+        for d2 in dice2.iter() {
+            if is_valid_dice_configuration(d1, d2) {
+                result += 1;
+            }
+        }
+    }
+
+    println!("Number of valid configurations of dice is {}", result);
 
     println!("Time passed: {:?}", Instant::now() - now);
 }