{"id":944,"date":"2021-03-18T22:01:00","date_gmt":"2021-03-18T16:31:00","guid":{"rendered":"https:\/\/www.codingbroz.com\/?p=944"},"modified":"2021-06-12T08:12:40","modified_gmt":"2021-06-12T02:42:40","slug":"how-to-implement-a-stack-using-linked-list","status":"publish","type":"post","link":"https:\/\/www.codingbroz.com\/how-to-implement-a-stack-using-linked-list\/","title":{"rendered":"How to implement a stack using linked list in Java &#038; C++"},"content":{"rendered":"\n<p>Hello Coders! Welcome to codingbroz and our Data Structures and algorithm interview series.<\/p>\n\n\n\n<p>Today, we are going to see an interesting problem commonly asked in coding interviews is <strong>How to implement a stack using linked list <\/strong>? We will also implement the code in Java as well as C++ programming language.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1200\" height=\"686\" src=\"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/03\/how-to-implement-a-stack-using-linked-list-in-java-and-c-codingbroz.png\" alt=\"How to implement a stack using linked list in Java &amp; C++\" class=\"wp-image-991\" srcset=\"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/03\/how-to-implement-a-stack-using-linked-list-in-java-and-c-codingbroz.png 1200w, https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/03\/how-to-implement-a-stack-using-linked-list-in-java-and-c-codingbroz-768x439.png 768w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/figure>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_65 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<label for=\"ez-toc-cssicon-toggle-item-662d8d944d5e5\" class=\"ez-toc-cssicon-toggle-label\"><label class=\"ez-toc-title\">Table of Contents<\/label>\n<span class=\"ez-toc-cssicon\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #0090ff;color:#0090ff\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #0090ff;color:#0090ff\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-662d8d944d5e5\" checked \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.codingbroz.com\/how-to-implement-a-stack-using-linked-list\/#Problem\" title=\"Problem :&nbsp;\">Problem :&nbsp;<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.codingbroz.com\/how-to-implement-a-stack-using-linked-list\/#Solution_%E2%80%93_How_to_implement_a_stack_using_linked_list\" title=\"Solution &#8211; How to implement a stack using linked list \">Solution &#8211; How to implement a stack using linked list <\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.codingbroz.com\/how-to-implement-a-stack-using-linked-list\/#Java\" title=\"Java \">Java <\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.codingbroz.com\/how-to-implement-a-stack-using-linked-list\/#C\" title=\"C++ \">C++ <\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Problem\"><\/span><strong>Problem :&nbsp;<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>The problem statement says that, you have to implement a stack using linked list.<\/p>\n\n\n\n<p>You have to implement the LIFO property of stack using the linked list data structure.<\/p>\n\n\n\n<p>You have to implement the following functions using a linked list which follows the LIFO property of stack :<\/p>\n\n\n\n<ul><li><strong>push() : <\/strong>This function should accept data in LIFO manner.<\/li><li><strong>pop() : <\/strong>This function should return and remove data in LIFO manner.<\/li><li><strong>peek() : <\/strong>This function should return the data in LIFO manner.<\/li><\/ul>\n\n\n\n<p><strong>Also Read : <\/strong><em><a href=\"https:\/\/www.codingbroz.com\/how-to-implement-a-queue-using-linked-list\/\" target=\"_blank\" data-type=\"URL\" data-id=\"https:\/\/www.codingbroz.com\/how-to-implement-a-queue-using-linked-list\/\" rel=\"noreferrer noopener\">How to implement a queue using linked list &#8211; Java &amp; C++<\/a><\/em><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Solution_%E2%80%93_How_to_implement_a_stack_using_linked_list\"><\/span><strong>Solution &#8211; How to implement a stack using linked list<\/strong> <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Java\"><\/span><strong>Java <\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"java\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ Java program to Implement a stack\n\/\/ using singly linked list\n\/\/ import package\nimport static java.lang.System.exit;\n\n\/\/ Create Stack Using Linked list\nclass StackUsingLinkedlist {\n\n\t\/\/ A linked list node\n\tprivate class Node {\n\n\t\tint data; \/\/ integer data\n\t\tNode link; \/\/ reference variable Node type\n\t}\n\t\/\/ create global top reference variable global\n\tNode top;\n\t\/\/ Constructor\n\tStackUsingLinkedlist()\n\t{\n\t\tthis.top = null;\n\t}\n\n\t\/\/ Utility function to add an element x in the stack\n\tpublic void push(int x) \/\/ insert at the beginning\n\t{\n\t\t\/\/ create new node temp and allocate memory\n\t\tNode temp = new Node();\n\n\t\t\/\/ check if stack (heap) is full. Then inserting an\n\t\t\/\/ element would lead to stack overflow\n\t\tif (temp == null) {\n\t\t\tSystem.out.print(\"\\nHeap Overflow\");\n\t\t\treturn;\n\t\t}\n\n\t\t\/\/ initialize data into temp data field\n\t\ttemp.data = x;\n\n\t\t\/\/ put top reference into temp link\n\t\ttemp.link = top;\n\n\t\t\/\/ update top reference\n\t\ttop = temp;\n\t}\n\n\t\/\/ Utility function to check if the stack is empty or not\n\tpublic boolean isEmpty()\n\t{\n\t\treturn top == null;\n\t}\n\n\t\/\/ Utility function to return top element in a stack\n\tpublic int peek()\n\t{\n\t\t\/\/ check for empty stack\n\t\tif (!isEmpty()) {\n\t\t\treturn top.data;\n\t\t}\n\t\telse {\n\t\t\tSystem.out.println(\"Stack is empty\");\n\t\t\treturn -1;\n\t\t}\n\t}\n\n\t\/\/ Utility function to pop top element from the stack\n\tpublic void pop() \/\/ remove at the beginning\n\t{\n\t\t\/\/ check for stack underflow\n\t\tif (top == null) {\n\t\t\tSystem.out.print(\"\\nStack Underflow\");\n\t\t\treturn;\n\t\t}\n\n\t\t\/\/ update the top pointer to point to the next node\n\t\ttop = (top).link;\n\t}\n\n\tpublic void display()\n\t{\n\t\t\/\/ check for stack underflow\n\t\tif (top == null) {\n\t\t\tSystem.out.printf(\"\\nStack Underflow\");\n\t\t\texit(1);\n\t\t}\n\t\telse {\n\t\t\tNode temp = top;\n\t\t\twhile (temp != null) {\n\n\t\t\t\t\/\/ print node data\n\t\t\t\tSystem.out.printf(\"%d->\", temp.data);\n\n\t\t\t\t\/\/ assign temp link to temp\n\t\t\t\ttemp = temp.link;\n\t\t\t}\n\t\t}\n\t}\n}\n\/\/ main class\npublic class CB {\n\tpublic static void main(String[] args)\n\t{\n\t\t\/\/ create Object of Implementing class\n\t\tStackUsingLinkedlist obj = new StackUsingLinkedlist();\n\t\t\/\/ insert Stack value\n\t\tobj.push(11);\n\t\tobj.push(22);\n\t\tobj.push(33);\n\t\tobj.push(44);\n\n\t\t\/\/ print Stack elements\n\t\tobj.display();\n\n\t\t\/\/ print Top element of Stack\n\t\tSystem.out.printf(\"\\nTop element is %d\\n\", obj.peek());\n\n\t\t\/\/ Delete top element of Stack\n\t\tobj.pop();\n\t\tobj.pop();\n\n\t\t\/\/ print Stack elements\n\t\tobj.display();\n\n\t\t\/\/ print Top element of Stack\n\t\tSystem.out.printf(\"\\nTop element is %d\\n\", obj.peek());\n\t}\n}\n\n<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"C\"><\/span><strong>C++ <\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ C++ program to Implement a stack \n\/\/using singly linked list \n#include &lt;bits\/stdc++.h> \nusing namespace std; \n \n\/\/ Declare linked list node \n \nstruct Node \n{ \n    int data; \n    struct Node* link; \n}; \n \nstruct Node* top; \n \n\/\/ Utility function to add an element \n\/\/ data in the stack insert at the beginning \nvoid push(int data) \n{ \n     \n    \/\/ Create new node temp and allocate memory \n    struct Node* temp; \n    temp = new Node(); \n \n    \/\/ Check if stack (heap) is full. \n    \/\/ Then inserting an element would \n    \/\/ lead to stack overflow \n    if (!temp)\n    { \n        cout &lt;&lt; \"\\nHeap Overflow\"; \n        exit(1); \n    } \n \n    \/\/ Initialize data into temp data field \n    temp->data = data; \n \n    \/\/ Put top pointer reference into temp link \n    temp->link = top; \n \n    \/\/ Make temp as top of Stack \n    top = temp; \n} \n \n\/\/ Utility function to check if \n\/\/ the stack is empty or not \nint isEmpty() \n{ \n    return top == NULL; \n} \n \n\/\/ Utility function to return top element in a stack \nint peek() \n{ \n     \n    \/\/ Check for empty stack \n    if (!isEmpty()) \n        return top->data; \n    else\n        exit(1); \n} \n \n\/\/ Utility function to pop top \n\/\/ element from the stack \nvoid pop() \n{ \n    struct Node* temp; \n \n    \/\/ Check for stack underflow \n    if (top == NULL) \n    { \n        cout &lt;&lt; \"\\nStack Underflow\" &lt;&lt; endl; \n        exit(1); \n    } \n    else\n    { \n         \n        \/\/ Top assign into temp \n        temp = top; \n \n        \/\/ Assign second node to top \n        top = top->link; \n \n        \/\/ Destroy connection between\n        \/\/ first and second \n        temp->link = NULL; \n \n        \/\/ Release memory of top node \n        free(temp); \n    } \n} \n \n\/\/ Function to print all the \n\/\/ elements of the stack \nvoid display() \n{ \n    struct Node* temp; \n \n    \/\/ Check for stack underflow \n    if (top == NULL)\n    { \n        cout &lt;&lt; \"\\nStack Underflow\"; \n        exit(1); \n    } \n    else\n    { \n        temp = top; \n        while (temp != NULL)\n        { \n \n            \/\/ Print node data \n            cout &lt;&lt; temp->data &lt;&lt; \"-> \"; \n \n            \/\/ Assign temp link to temp \n            temp = temp->link; \n        } \n    } \n} \n \n\/\/ Driver Code \nint main() \n{ \n     \n    \/\/ Push the elements of stack \n    push(11); \n    push(22); \n    push(33); \n    push(44); \n \n    \/\/ Display stack elements \n    display(); \n \n    \/\/ Print top element of stack \n    cout &lt;&lt; \"\\nTop element is \"\n         &lt;&lt; peek() &lt;&lt; endl; \n \n    \/\/ Delete top elements of stack \n    pop(); \n    pop(); \n \n    \/\/ Display stack elements \n    display(); \n \n    \/\/ Print top element of stack \n    cout &lt;&lt; \"\\nTop element is \"\n         &lt;&lt; peek() &lt;&lt; endl; \n          \n    return 0; \n} \n<\/pre>\n\n\n\n<p><strong>More Problems related to Linked List &#8211;<\/strong><\/p>\n\n\n\n<ul><li><strong><a href=\"https:\/\/www.codingbroz.com\/find-the-middle-of-a-linked-list\/\" target=\"_blank\" data-type=\"URL\" data-id=\"https:\/\/www.codingbroz.com\/find-the-middle-of-a-linked-list\/\" rel=\"noreferrer noopener\">How to find middle in a LinkedList ?<\/a><\/strong><\/li><li><strong><a href=\"https:\/\/www.codingbroz.com\/how-to-implement-a-queue-using-linked-list\/\" target=\"_blank\" data-type=\"URL\" data-id=\"https:\/\/www.codingbroz.com\/how-to-implement-a-queue-using-linked-list\/\" rel=\"noreferrer noopener\">How to implement queue data structure using linked list ?<\/a><\/strong><\/li><li><strong>How to find the k-th element from the end in a given linked list ?<\/strong><\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Hello Coders! Welcome to codingbroz and our Data Structures and algorithm interview series. Today, we are going to see an interesting problem commonly asked in coding interviews is How to implement a stack using linked list ?<\/p>\n","protected":false},"author":3,"featured_media":991,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"default","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[115],"tags":[126,123,125,122,124,116,113,114,127],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/03\/how-to-implement-a-stack-using-linked-list-in-java-and-c-codingbroz.png","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/944"}],"collection":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/comments?post=944"}],"version-history":[{"count":5,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/944\/revisions"}],"predecessor-version":[{"id":3198,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/944\/revisions\/3198"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/media\/991"}],"wp:attachment":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/media?parent=944"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/categories?post=944"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/tags?post=944"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}