backend by zatzou

src/main.rs

@@ -1,3 +1,51 @@
+use std::collections::BTreeMap;
+use std::collections::btree_map::Entry;
+
 fn main() {
-    println!("Hello, world!");
+    let dice = [6, 6, 6, 6, 7];
+
+    // i need 2 otherwise the for loops below break
+    let comb = combinations(&dice);
+    let comb2 = comb.clone();
+
+    // below code gets total for all values
+    let mut total = 0;
+
+
+    for i in comb {
+        total += i.1;
+    }
+    for i in comb2 {
+        println!("{i:?}");
+        println!("{total}")
+    }
+}
+
+fn combinations(dice: &[u32]) -> BTreeMap<u32, u32> {
+    let mut out = BTreeMap::new();
+
+    recursive(dice, &mut out, &[]);
+
+    out
+}
+
+fn recursive(dice: &[u32], out: &mut BTreeMap<u32, u32>, cur: &[u32]) {
+    let d = dice[0];
+
+    for i in 1..=d {
+        if dice.len() >= 2 {
+            recursive(&dice[1..], out, &[cur, &[i]].concat());
+        } else {
+            let temp = cur.iter().sum::<u32>() + i;
+
+            match out.entry(temp) {
+                Entry::Vacant(e) => {
+                    e.insert(1);
+                },
+                Entry::Occupied(e) => {
+                    *e.into_mut() += 1;
+                }
+            }
+        }
+    }
 }