Added solution of problem 1608

Author: kurpenok

src/solutions/mod.rs

@@ -343,6 +343,7 @@ pub mod s1588_sum_of_all_odd_length_subarrays;
 pub mod s1592_rearrange_spaces_between_words;
 pub mod s1598_crawler_log_folder;
 pub mod s1603_design_parking_system;
+pub mod s1608_special_array_with_x_elements_greater_than_or_equal_x;
 pub mod s1619_mean_of_array_after_removing_some_elements;
 pub mod s1935_maximum_number_of_words_you_can_type;
 pub mod s1957_delete_characters_to_make_fancy_string;

src/solutions/s1608_special_array_with_x_elements_greater_than_or_equal_x.rs

@@ -0,0 +1,41 @@
+pub fn special_array(nums: Vec<i32>) -> i32 {
+    let arr_count = nums.iter().fold([0; 1001], |mut acc, &x| {
+        acc[x as usize] += 1;
+        acc
+    });
+    let mut prev_sum = 0;
+    let l = nums.len() as i32;
+
+    for i in 0..=l {
+        let after_sum = l - prev_sum;
+        prev_sum += arr_count[i as usize];
+
+        if after_sum == i {
+            return i;
+        } else if prev_sum == l {
+            break;
+        }
+    }
+
+    -1
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_case_1() {
+        assert_eq!(special_array(vec![3, 5]), 2);
+    }
+
+    #[test]
+    fn test_case_2() {
+        assert_eq!(special_array(vec![0, 0]), -1);
+    }
+
+    #[test]
+    fn test_case_3() {
+        assert_eq!(special_array(vec![0, 4, 3, 0, 4]), 3);
+    }
+}