# Java Exercises: Find the maximum and minimum elements in a stack

## Java Stack: Exercise-5 with Solution

Write a Java program to find the maximum and minimum elements in a stack.

Sample Solution:

Java Code:

``````import java.util.Scanner;
public class Stack {
private int[] arr;
private int top;

// Constructor to initialize the stack
public Stack(int size) {
arr = new int[size];
top = -1;
}

// Method to push an element onto the stack
public void push(int num) {
if (top == arr.length - 1) {
System.out.println("Stack is full");
} else {
top++;
arr[top] = num;
}
}

// Method to pop an element from the stack
public int pop() {
if (top == -1) {
System.out.println("Stack Underflow");
return -1;
} else {
int poppedElement = arr[top];
top--;
return poppedElement;
}
}

// Method to get the top element of the stack
public int peek() {
if (top == -1) {
System.out.println("Stack is empty");
return -1;
} else {
return arr[top];
}
}

// Method to check if the stack is empty
public boolean isEmpty() {
}
// Method to get the maximum value
public int get_Max() {
if (top == -1) {
System.out.println("Stack is empty");
return -1;
}

int max = arr;

for (int i = 1; i <= top; i++) {
if (arr[i] > max) {
max = arr[i];
}
}

return max;
}

// Method to get the minimum value
public int get_Min() {
if (top == -1) {
System.out.println("Stack is empty");
return -1;
}

int min = arr;

for (int i = 1; i <= top; i++) {
if (arr[i] < min) {
min = arr[i];
}
}

return min;
}

public void display() {
if (top == -1) {
System.out.println("Stack is empty");
} else {
System.out.print("Stack elements: ");
for (int i = top; i >= 0; i--) {
System.out.print(arr[i] + " ");
}
System.out.println();
}
}

public static void main(String[] args) {
System.out.println("Initialize a stack:");
Stack stack = new Stack(10);
System.out.println("\nInput some elements on the stack:");
stack.push(1);
stack.push(3);
stack.push(2);
stack.push(0);
stack.push(7);
stack.push(5);
stack.push(-1);
stack.display();
int max_val = stack.get_Max();
System.out.println("\nMaximum value in stack: " + max_val);
int min_val = stack.get_Min();
System.out.println("\nMinimum value in stack: " + min_val);
}
}
```
```

Sample Output:

```Initialize a stack:

Input some elements on the stack:
Stack elements: -1 5 7 0 2 3 1

Maximum value in stack: 7

Minimum value in stack: -1
```

Flowchart:   Live Demo:

Java Code Editor:

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Java Stack Previous: Reverse the elements of a stack.
Java Stack Exercises Next: Remove all the elements from a stack.

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