1830. Minimum Number of Operations to Make String Sorted: RETRY

src/solution/mod.rs

@@ -1379,3 +1379,4 @@ mod s1825_finding_mk_average;
 mod s1827_minimum_operations_to_make_the_array_increasing;
 mod s1828_queries_on_number_of_points_inside_a_circle;
 mod s1829_maximum_xor_for_each_query;
+mod s1830_minimum_number_of_operations_to_make_string_sorted;

src/solution/s1830_minimum_number_of_operations_to_make_string_sorted.rs

@@ -0,0 +1,77 @@
+/**
+ * [1830] Minimum Number of Operations to Make String Sorted
+ *
+ * You are given a string s (0-indexed)​​​​​​. You are asked to perform the following operation on s​​​​​​ until you get a sorted string:
+ * <ol>
+ * 	Find the largest index i such that 1 <= i < s.length and s[i] < s[i - 1].
+ * 	Find the largest index j such that i <= j < s.length and s[k] < s[i - 1] for all the possible values of k in the range [i, j] inclusive.
+ * 	Swap the two characters at indices i - 1​​​​ and j​​​​​.
+ * 	Reverse the suffix starting at index i​​​​​​.
+ * </ol>
+ * Return the number of operations needed to make the string sorted. Since the answer can be too large, return it modulo 10^9 + 7.
+ *  
+ * Example 1:
+ *
+ * Input: s = "cba"
+ * Output: 5
+ * Explanation: The simulation goes as follows:
+ * Operation 1: i=2, j=2. Swap s[1] and s[2] to get s="cab", then reverse the suffix starting at 2. Now, s="cab".
+ * Operation 2: i=1, j=2. Swap s[0] and s[2] to get s="bac", then reverse the suffix starting at 1. Now, s="bca".
+ * Operation 3: i=2, j=2. Swap s[1] and s[2] to get s="bac", then reverse the suffix starting at 2. Now, s="bac".
+ * Operation 4: i=1, j=1. Swap s[0] and s[1] to get s="abc", then reverse the suffix starting at 1. Now, s="acb".
+ * Operation 5: i=2, j=2. Swap s[1] and s[2] to get s="abc", then reverse the suffix starting at 2. Now, s="abc".
+ *
+ * Example 2:
+ *
+ * Input: s = "aabaa"
+ * Output: 2
+ * Explanation: The simulation goes as follows:
+ * Operation 1: i=3, j=4. Swap s[2] and s[4] to get s="aaaab", then reverse the substring starting at 3. Now, s="aaaba".
+ * Operation 2: i=4, j=4. Swap s[3] and s[4] to get s="aaaab", then reverse the substring starting at 4. Now, s="aaaab".
+ *
+ *  
+ * Constraints:
+ *
+ * 	1 <= s.length <= 3000
+ * 	s​​​​​​ consists only of lowercase English letters.
+ *
+ */
+pub struct Solution {}
+
+// problem: https://leetcode.com/problems/minimum-number-of-operations-to-make-string-sorted/
+// discuss: https://leetcode.com/problems/minimum-number-of-operations-to-make-string-sorted/discuss/?currentPage=1&orderBy=most_votes&query=
+
+// submission codes start here
+
+impl Solution {
+    pub fn make_string_sorted(s: String) -> i32 {
+        0
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn test_1830_example_1() {
+        let s = "cba".to_string();
+
+        let result = 5;
+
+        assert_eq!(Solution::make_string_sorted(s), result);
+    }
+
+    #[test]
+    #[ignore]
+    fn test_1830_example_2() {
+        let s = "aabaa".to_string();
+
+        let result = 2;
+
+        assert_eq!(Solution::make_string_sorted(s), result);
+    }
+}