|158|[Read N Characters Given Read4 II - Call multiple times](https://leetcode.com/problems/read-n-characters-given-read4-ii-call-multiple-times/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_158.java)| O(n)|O(1)| Hard|

|157|[Read N Characters Given Read4](https://leetcode.com/problems/read-n-characters-given-read4/)|[Solution](../master/src/main/java/com/fishercoder/solutions/ReadNCharactersGivenRead4.java)| O(n)|O(1)| Easy|

|156|[Binary Tree Upside Down](https://leetcode.com/problems/binary-tree-upside-down/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_156.java)| O(n)|O(h) | Medium| Tree, Recursion

|155|[Min Stack](https://leetcode.com/problems/min-stack/)|[Solution](../master/src/main/java/com/fishercoder/solutions/MinStack.java)| O(1)|O(n) | Easy| Stack

|155|[Min Stack](https://leetcode.com/problems/min-stack/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_155.java)| O(1)|O(n) | Easy| Stack

|154|[Find Minimum in Rotated Sorted Array II](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_154.java)| O(logn)|O(1) | Hard| Array, Binary Search

|153|[Find Minimum in Rotated Sorted Array](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_153.java)| O(logn)|O(1) | Medium| Array, Binary Search

|152|[Maximum Product Subarray](https://leetcode.com/problems/maximum-product-subarray/)|[Solution](../master/src/main/java/com/fishercoder/solutions/MaximumProductSubarray.java)| O(n)|O(1) | Medium| Array

publicclassMinStack {

publicclass_155 {

privateStack<Integer>stack;

privateintmin;

publicMinStack() {

public_155() {

stack =newStack();

min =Integer.MAX_VALUE;

}