add: 209

Author: huyjs9

README.md

@@ -12,6 +12,7 @@
 | 120  | [Triangle](./src/120.triangle.py)                                                                                          | Medium | O(N^2)       | O(N^2)     | Array, Dynamic Programming                                          | DP (Min - Max)                |
 | 198  | [House Robber](./src/198.house-robber.py)                                                                                  | Medium | O(N)         | O(N)       | Array, Dynamic Programming                                          | Recursion                     |
 | 200  | [Number of Islands](./src/200.number-of-islands.py)                                                                        | Medium | O(R\*C)      | O(R\*C)    | Array, Depth-First Search, Breadth-First Search, Union Find, Matrix | DP                            |
+| 209  | [Minimum Size Subarray Sum](./src/209.minimum-size-subarray-sum.py)                                                        | Medium | O(N^2)       | O(1)       | Array, Binary Search, Sliding Window, Prefix Sum                    |                               |
 | 221  | [Maximal Square](./src/221.maximal-square.py)                                                                              | Medium | O(R\*C)      | O(1)       | Array, Dynamic Programming, Matrix                                  | DP (Min - Max)                |
 | 279  | [Perfect Squares](./src/279.perfect-squares.py)                                                                            | Medium | O(N\*log(N)) | O(N)       | Math, Dynamic Programming, BFS                                      | DP (Min - Max)                |
 | 322  | [Coin Change](./src/322.coin-change.py)                                                                                    | Medium | O(A\*N)      | O(A)       | Array, Dynamic Programming, Breadth-First Search                    | DP (Min - Max)                |

src/209.minimum-size-subarray-sum.py

@@ -0,0 +1,47 @@
+# Level: Medium
+# TAGS: Array, Binary Search, Sliding Window, Prefix Sum
+
+from typing import List
+
+
+class Solution:
+    # Time: O(N^2) | Space: O(1)
+    def minSubArrayLen(self, target: int, nums: List[int]) -> int:
+        left, total, n = 0, 0, len(nums)
+
+        min_len = float("inf")
+
+        for right in range(n):
+            total += nums[right]
+
+            while total >= target:
+                min_len = min(min_len, right - left + 1)
+                total -= nums[left]
+                left += 1
+
+        return 0 if min_len == float("inf") else min_len
+
+
+tests = [
+    (
+        (
+            7,
+            [2, 3, 1, 2, 4, 3],
+        ),
+        2,
+    ),
+    (
+        (
+            4,
+            [1, 4, 4],
+        ),
+        1,
+    ),
+    (
+        (
+            11,
+            [1, 1, 1, 1, 1, 1, 1, 1],
+        ),
+        0,
+    ),
+]