LC 3097. Shortest Subarray With OR at Least K II (Rust)

Author: raul-sauco

README.md

@@ -782,6 +782,7 @@ to the solution in this repository.
 | [3043. Find the Length of the Longest Common Prefix][lc3043]                                  | 🟠 Medium  | [![rust](res/rs.png)][lc3043rs]                                                                       |
 | [3068. Find the Maximum Sum of Node Values][lc3068]                                           | 🔴 Hard    | [![rust](res/rs.png)][lc3068rs]                                                                       |
 | [3075. Maximize Happiness of Selected Children][lc3075]                                       | 🟠 Medium  | [![rust](res/rs.png)][lc3075rs]                                                                       |
+| [3097. Shortest Subarray With OR at Least K II][lc3097]                                       | 🟠 Medium  | [![rust](res/rs.png)][lc3097rs]                                                                       |
 | [3110. Score of a String][lc3110]                                                             | 🟢 Easy    | [![rust](res/rs.png)][lc3110rs]                                                                       |
 | [3133. Minimum Array End][lc3133]                                                             | 🟠 Medium  | [![rust](res/rs.png)][lc3133rs]                                                                       |
 | [3217. Delete Nodes From Linked List Present in Array][lc3217]                                | 🟠 Medium  | [![python](res/py.png)][lc3217py]                                                                     |
@@ -2502,6 +2503,8 @@ to the solution in this repository.
 [lc3068rs]: leetcode/find-the-maximum-sum-of-node-values.rs
 [lc3075]: https://leetcode.com/problems/maximize-happiness-of-selected-children/
 [lc3075rs]: leetcode/maximize-happiness-of-selected-children.rs
+[lc3097]: https://leetcode.com/problems/shortest-subarray-with-or-at-least-k-ii/
+[lc3097rs]: leetcode/shortest-subarray-with-or-at-least-k-ii.rs
 [lc3110]: https://leetcode.com/problems/score-of-a-string/
 [lc3110rs]: leetcode/score-of-a-string.rs
 [lc3133]: https://leetcode.com/problems/minimum-array-end/

leetcode/shortest-subarray-with-or-at-least-k-ii.rs

@@ -0,0 +1,99 @@
+// 3097. Shortest Subarray With OR at Least K II
+// 🟠 Medium
+//
+// https://leetcode.com/problems/shortest-subarray-with-or-at-least-k-ii/
+//
+// Tags: Array - Bit Manipulation - Sliding Window
+
+struct Solution;
+impl Solution {
+    /// A nice variation of the sliding window problem where we need to figure out how to remove
+    /// digits from the left when shrinking the window. To do it, we need to keep track of the
+    /// number of times that we have seen a bit in values inside the window, when we pop a value,
+    /// we need to remove one from that bit count, when we get to 0, that bit will not be set in
+    /// the current value of the window's OR.
+    ///
+    /// Time complexity: O(n) - We visit each value in the input twice, for each, we iterate over
+    /// the set bits in constant time because they max at 30.
+    /// Space complexity: O(1) - One array of size 32 and a few integers.
+    ///
+    /// Runtime 23 ms Beats 100%
+    /// Memory 4.06 MB Beats 66%
+    pub fn minimum_subarray_length(nums: Vec<i32>, k: i32) -> i32 {
+        let mut l = 0;
+        let mut res = usize::MAX;
+        let mut bits = [0; 32];
+        let mut mask;
+        let mut int_val = 0;
+        for (r, &num) in nums.iter().enumerate() {
+            // Print integer as binary digits.
+            // println!("num: {:#032b} - {}", num, num);
+            for i in 0..32 {
+                mask = 1 << i;
+                // If this bit is set in the current num.
+                if num & mask > 0 {
+                    // Update the count of numbers with this bit set.
+                    bits[i] += 1;
+                    // If we go from 0 to 1, update the int value.
+                    if bits[i] == 1 {
+                        int_val += mask;
+                    }
+                }
+            }
+            // Now shrink the window as much as we can.
+            while int_val >= k && l <= r {
+                res = res.min(1 + r - l);
+                for i in 0..32 {
+                    mask = 1 << i;
+                    if nums[l] & mask > 0 {
+                        bits[i] -= 1;
+                        if bits[i] == 0 {
+                            int_val -= mask;
+                        }
+                    }
+                }
+                l += 1;
+            }
+        }
+        if res == usize::MAX {
+            -1
+        } else {
+            res as i32
+        }
+    }
+}
+
+// Tests.
+fn main() {
+    let tests = [
+        (vec![1, 2], 0, 1),
+        (vec![1, 2, 3], 2, 1),
+        (vec![2, 1, 8], 10, 3),
+        (vec![1, 2, 32, 21], 55, 3),
+    ];
+    println!("\n\x1b[92m» Running {} tests...\x1b[0m", tests.len());
+    let mut success = 0;
+    for (i, t) in tests.iter().enumerate() {
+        let res = Solution::minimum_subarray_length(t.0.clone(), t.1);
+        if res == t.2 {
+            success += 1;
+            println!("\x1b[92m✔\x1b[95m Test {} passed!\x1b[0m", i);
+        } else {
+            println!(
+                "\x1b[31mx\x1b[95m Test {} failed expected: {:?} but got {}!!\x1b[0m",
+                i, t.2, res
+            );
+        }
+    }
+    println!();
+    if success == tests.len() {
+        println!("\x1b[30;42m✔ All tests passed!\x1b[0m")
+    } else if success == 0 {
+        println!("\x1b[31mx \x1b[41;37mAll tests failed!\x1b[0m")
+    } else {
+        println!(
+            "\x1b[31mx\x1b[95m {} tests failed!\x1b[0m",
+            tests.len() - success
+        )
+    }
+}