20250307 finished.

src/problem/mod.rs

@@ -522,3 +522,5 @@ mod p1745_palindrome_partitioning_iv;
 mod p1328_break_a_palindrome;
 
 mod p2588_count_the_number_of_beautiful_subarrays;
+
+mod p2597_the_number_of_beautiful_subsets;

src/problem/p2597_the_number_of_beautiful_subsets.rs

@@ -0,0 +1,64 @@
+/**
+ * [2597] The Number of Beautiful Subsets
+ */
+pub struct Solution {}
+
+// submission codes start here
+use std::collections::{BTreeMap, HashMap};
+
+impl Solution {
+    pub fn beautiful_subsets(nums: Vec<i32>, k: i32) -> i32 {
+        let mut map = HashMap::new();
+
+        for i in nums {
+            let value = i % k;
+            let entry = map.entry(value).or_insert(BTreeMap::new());
+            let group_entry = entry.entry(i).or_insert(0);
+            *group_entry += 1;
+        }
+
+        let mut result = 1;
+
+        for group in map.values() {
+            let n = group.len();
+            // (x, y) x表示不选择第i个数
+            // y表示选择第i个数
+            let mut dp = vec![(0, 0); n];
+            // 懒得用迭代器移来移去
+            // 直接复制到数组开干
+            let array: Vec<(i32, i32)> = group.iter().map(|(x, y)| (*x, *y)).collect();
+
+            for (i, &(key, count)) in array.iter().enumerate() {
+                if i == 0 {
+                    dp[0].0 = 1;
+                    dp[0].1 = (1 << count) - 1;
+                } else {
+                    dp[i].0 = dp[i - 1].0 + dp[i - 1].1;
+
+                    if key - array[i - 1].0 == k {
+                        dp[i].1 = dp[i - 1].0 * ((1 << count) - 1);
+                    } else {
+                        dp[i].1 = (dp[i - 1].0 + dp[i - 1].1) * ((1 << count) - 1);
+                    }
+                }
+            }
+
+            result *= dp[n - 1].0 + dp[n - 1].1;
+        }
+
+        result - 1
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_2597() {
+        assert_eq!(4, Solution::beautiful_subsets(vec![2, 4, 6], 2));
+        assert_eq!(1, Solution::beautiful_subsets(vec![1], 1));
+    }
+}