Apr 21

Author: siddydutta

2025-04-April-LeetCoding-Challenge/Count the Hidden Sequences.py

@@ -0,0 +1,30 @@
+class Solution:
+    def numberOfArrays(self, differences: list[int], lower: int, upper: int) -> int:
+        _min, _max = 0, 0
+        curr = 0
+        for diff in differences:
+            curr += diff
+            _min = min(_min, curr)
+            _max = max(_max, curr)
+        return max((upper - lower) - (_max - _min) + 1, 0)
+
+
+def main():
+    differences = [1, -3, 4]
+    lower = 1
+    upper = 6
+    assert Solution().numberOfArrays(differences, lower, upper) == 2
+
+    differences = [3, -4, 5, 1, -2]
+    lower = -4
+    upper = 5
+    assert Solution().numberOfArrays(differences, lower, upper) == 4
+
+    differences = [4, -7, 2]
+    lower = 3
+    upper = 6
+    assert Solution().numberOfArrays(differences, lower, upper) == 0
+
+
+if __name__ == '__main__':
+    main()

2025-04-April-LeetCoding-Challenge/README.md

@@ -24,7 +24,7 @@
 | April 18 | [38. Count and Say](https://leetcode.com/problems/count-and-say/) | Medium | Solved |
 | April 19 | [2563. Count the Number of Fair Pairs](https://leetcode.com/problems/count-the-number-of-fair-pairs/) | Medium | Solved |
 | April 20 | [781. Rabbits in Forest](https://leetcode.com/problems/rabbits-in-forest/) | Medium | Solved |
-| April 21 | []() |  |  |
+| April 21 | [2145. Count the Hidden Sequences](https://leetcode.com/problems/count-the-hidden-sequences/) | Medium | Solved |
 | April 22 | []() |  |  |
 | April 23 | []() |  |  |
 | April 24 | []() |  |  |
@@ -40,5 +40,5 @@
 | Level  | Problems | Solved | Unsolved |
 | ---    | --- | --- | --- |
 | Easy   | 6 | 6 | 0 |
-| Medium | 11 | 8 | 3 |
+| Medium | 12 | 9 | 3 |
 | Hard   | 3 | 0 | 3 |