Merge pull request #990 from mintheon/main

[mintheon] Week 09

Author: SamTheKorean

find-minimum-in-rotated-sorted-array/mintheon.java

@@ -0,0 +1,13 @@
+class Solution {
+  // 시간복잡도: O(n)
+  // 공간복잡도: O(1)
+  public int findMin(int[] nums) {
+    for(int i = 1; i < nums.length; i++) {
+      if(nums[i - 1] > nums[i]) {
+        return nums[i];
+      }
+    }
+
+    return nums[0];
+  }
+}

linked-list-cycle/mintheon.java

@@ -0,0 +1,28 @@
+/**
+ * Definition for singly-linked list.
+ * class ListNode {
+ *     int val;
+ *     ListNode next;
+ *     ListNode(int x) {
+ *         val = x;
+ *         next = null;
+ *     }
+ * }
+ */
+//시간복잡도: O(n)
+//공간복잡도: O(1)
+public class Solution {
+  public boolean hasCycle(ListNode head) {
+    ListNode slow = head;
+    ListNode fast = head;
+
+    while(fast != null && fast.next != null) {
+      slow = slow.next;
+      fast = fast.next.next;
+
+      if(slow == fast) return true;
+    }
+
+    return false;
+  }
+}

maximum-product-subarray/mintheon.java

@@ -0,0 +1,26 @@
+class Solution {
+  //시간복잡도: O(n)
+  //공간복잡도: O(n)
+  public int maxProduct(int[] nums) {
+    int[] maxValue = new int[nums.length];
+    int[] minValue = new int[nums.length];
+
+    maxValue[0] = nums[0];
+    minValue[0] = nums[0];
+
+    for(int i = 1; i < nums.length; i++) {
+      int value1 = maxValue[i - 1] * nums[i];
+      int value2 = minValue[i - 1] * nums[i];
+
+      maxValue[i] = Math.max(Math.max(value1, value2), nums[i]);
+      minValue[i] = Math.min(Math.min(value1, value2), nums[i]);
+    }
+
+    int result = Integer.MIN_VALUE;
+    for(int i = 0; i < nums.length; i++) {
+      result = Math.max(result, maxValue[i]);
+    }
+
+    return result;
+  }
+}