Merge pull request #257 from ben1009/3151

feat: 3151

Author: mergify[bot]

src/problem/mod.rs

@@ -72,6 +72,7 @@ pub mod p2938_separate_black_and_white_balls;
 pub mod p2956_find_common_elements_between_two_arrays;
 pub mod p2974_minimum_number_game;
 pub mod p3033_modify_the_matrix;
+pub mod p3151_special_array_i;
 pub mod p3153_sum_of_digit_differences_of_all_pairs;
 pub mod p3174_clear_digits;
 pub mod p3226_number_of_bit_changes_to_make_two_integers_equal;

src/problem/p3151_special_array_i.rs

@@ -0,0 +1,74 @@
+// An array is considered special if every pair of its adjacent elements contains two numbers with
+// different parity.
+
+// You are given an array of integers nums. Return true if nums is a special array, otherwise,
+// return false.
+
+// Example 1:
+
+// Input: nums = [1]
+
+// Output: true
+
+// Explanation:
+
+// There is only one element. So the answer is true.
+
+// Example 2:
+
+// Input: nums = [2,1,4]
+
+// Output: true
+
+// Explanation:
+
+// There is only two pairs: (2,1) and (1,4), and both of them contain numbers with different parity.
+// So the answer is true.
+
+// Example 3:
+
+// Input: nums = [4,3,1,6]
+
+// Output: false
+
+// Explanation:
+
+// nums[1] and nums[2] are both odd. So the answer is false.
+
+// Constraints:
+
+// 1 <= nums.length <= 100
+// 1 <= nums[i] <= 100
+
+// https://leetcode.com/problems/special-array-with-x-elements-greater-than-x
+// https://leetcode.com/problems/special-array-with-x-elements-greater-than-x/discuss/?currentPage=1&orderBy=most_votes&query=
+
+pub struct Solution {}
+
+impl Solution {
+    pub fn is_array_special(nums: Vec<i32>) -> bool {
+        if nums.len() == 1 {
+            return true;
+        }
+
+        for i in 1..nums.len() {
+            if nums[i] % 2 == nums[i - 1] % 2 {
+                return false;
+            }
+        }
+
+        true
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_3151() {
+        assert!(Solution::is_array_special(vec![1]));
+        assert!(Solution::is_array_special(vec![2, 1, 4]));
+        assert!(!Solution::is_array_special(vec![4, 3, 1, 6]));
+    }
+}