{"id":10068,"date":"2025-09-11T16:40:25","date_gmt":"2025-09-11T11:10:25","guid":{"rendered":"https:\/\/namastedev.com\/blog\/?p=10068"},"modified":"2025-09-11T16:48:19","modified_gmt":"2025-09-11T11:18:19","slug":"buy-sellstock","status":"publish","type":"post","link":"https:\/\/namastedev.com\/blog\/buy-sellstock\/","title":{"rendered":"Best Time to Buy and Sell Stock II"},"content":{"rendered":"\n<!-- Best stock 5 -->\n<!-- PrismJS for Syntax Highlighting -->\n<link href=\"https:\/\/cdn.jsdelivr.net\/npm\/prismjs@1.29.0\/themes\/prism-tomorrow.min.css\" rel=\"stylesheet\">\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/prismjs@1.29.0\/prism.min.js\"><\/script>\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/prismjs@1.29.0\/plugins\/autoloader\/prism-autoloader.min.js\"><\/script>\n\n<style>\n.wp_blog_theme {\n  --primary: #E58C32;\n  --secondary: #030302;\n  --light-bg: #fef9f4;\n  --text-dark: #2d2d2d;\n  --tab-radius: 12px;\n  --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);\n  --code-bg: #001f3f;\n  --code-text: #d4f1ff;\n}\n\n.wp_blog_container {\n  font-family: 'Segoe UI', sans-serif;\n  background: var(--light-bg);\n  margin: 0;\n  padding: 0;\n  color: var(--text-dark);\n}\n\n\/* Heading *\/\n.wp_blog_main-heading {\n  text-align: center;\n  font-size: 2.4rem;\n  color: var(--primary);\n  margin-top: 2.5rem;\n  font-weight: bold;\n}\n\n\/* Explanation Card *\/\n.wp_blog_explanation,\n.wp_blog_code-tabs-container {\n  max-width: 940px;\n  margin: 2rem auto;\n  padding: 2rem;\n  background: white;\n  border-radius: var(--tab-radius);\n  box-shadow: var(--shadow);\n}\n\n\/* Text and Visuals *\/\n.wp_blog_explanation h2 {\n  font-size: 1.4rem;\n  color: var(--primary);\n  margin-bottom: 0.5rem;\n}\n\n.wp_blog_explanation p,\n.wp_blog_explanation li {\n  font-size: 1.05rem;\n  line-height: 1.7;\n  margin: 0.5rem 0;\n}\n\n.wp_blog_explanation code {\n  background: #fef9f4;   \/* light bg instead of dark blue *\/\n  color: #E58C32;        \/* brand orange *\/\n  padding: 3px 6px;\n  border-radius: 4px;\n  font-family: 'Courier New', monospace;\n  font-weight: 600;      \/* optional, makes it pop *\/\n}\n\n.wp_blog_explanation img {\n  max-width: 100%;\n  border-radius: var(--tab-radius);\n  margin-top: 1rem;\n  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);\n}\n\n\/* Tab Buttons *\/\n.wp_blog_code-tabs-header {\n  display: flex;\n  flex-wrap: wrap;\n  gap: 0.5rem;\n  margin-bottom: 1rem;\n}\n\n.wp_blog_code-tab-button {\n  padding: 0.6rem 1.2rem;\n  border: 1px solid var(--primary);\n  background: white;\n  color: var(--primary);\n  border-radius: 50px;\n  font-weight: 600;\n  cursor: pointer;\n  transition: all 0.3s ease;\n}\n\n.wp_blog_code-tab-button:hover {\n  background: var(--secondary);\n}\n\n.wp_blog_code-tab-button.active {\n  background: var(--primary);\n  color: white;\n}\n\n\/* Code Content *\/\n.wp_blog_code-tab-content {\n  display: none;\n  background: var(--code-bg);\n  border-radius: var(--tab-radius);\n}\n\n.wp_blog_code-tab-content.active {\n  display: block;\n}\n\n.wp_blog_code-tab-content pre {\n  margin: 0;\n  padding: 1.5rem;\n  font-size: 1rem;\n  overflow-x: auto;\n  background: var(--code-bg);\n  border-radius: var(--tab-radius);\n  color: var(--code-text);\n}\n\n\/* Dark mode variables *\/\n.wp_blog_theme.dark-mode {\n  --light-bg: #121212;\n  --text-dark: #f5f5f5;\n  --shadow: 0 4px 12px rgba(255, 255, 255, 0.08);\n  --code-bg: #1e1e1e;\n  --code-text: #c5f0ff;\n}\n\n.wp_blog_theme.dark-mode .wp_blog_explanation {\n  background: #1e1e1e;\n}\n\n\/* Dark mode code highlight *\/\n.wp_blog_theme.dark-mode .wp_blog_explanation code {\n  background: #333;\n  color: #ffd27f;\n}\n\n.wp_blog_theme {\n  position: relative; \/* makes it the reference for absolute children *\/\n}\n\n.wp_blog_toggle-btn {\n  position: absolute;\n  top: 1rem;\n  right: 1rem;\n  z-index: 9999;\n  padding: 0.5rem 0.8rem;\n  border-radius: 10%;\n  background: var(--primary);\n  color: white;\n  font-weight: bold;\n  cursor: pointer;\n  border: none;\n  box-shadow: var(--shadow);\n  transition: background 0.3s, transform 0.2s;\n}\n\n.wp_blog_toggle-btn:hover {\n  background: #cc772e;\n}\n\n.wp_blog_theme.dark-mode .wp_blog_code-tabs-container {\n  background: #1e1e1e;\n}\n<\/style>\n\n<div class=\"wp_blog_container wp_blog_theme\">\n  <button id=\"blogNotesThemeToggle\" class=\"wp_blog_toggle-btn\">\ud83c\udf19<\/button>\n  <h1 class=\"wp_blog_main-heading\"><\/h1>\n\n  <div class=\"wp_blog_explanation\">\n    <h2>Problem Statement:<\/h2>\n    <p>\n        You are given an integer array <code>prices<\/code> where <code>prices[i]<\/code> is the price of a given stock on the <code>i<sup>th<\/sup><\/code> day.\n    <\/p>\n\n    <p>\n        On each day, you may decide to buy and\/or sell the stock. You can only hold <strong>at most one<\/strong> share of the stock at any time. However, you can buy it then immediately sell it on the <strong>same day<\/strong>.\n    <\/p>\n\n    <p>\n        Find and return <i>the <strong>maximum<\/strong> profit you can achieve<\/i>.\n    <\/p>\n\n    <h3>Example 1:<\/h2>\n    <p><strong>Input:<\/strong> prices = [7,1,5,3,6,4]\n<\/p>\n    <p><strong>Output:<\/strong> 7<\/p>\n    <p><strong>Explanation:<\/strong>\n        Buy on day 2 (price = 1) and sell on day 3 (price = 5), profit = 5-1 = 4.\n        Then buy on day 4 (price = 3) and sell on day 5 (price = 6), profit = 6-3 = 3.\n        Total profit is 4 + 3 = 7.\n    <\/p>\n\n    <h3>Example 2:<\/h3>\n    <p><strong>Input: <\/strong>prices = [1,2,3,4,5]<\/p>\n    <p><strong>Output: <\/strong>4<\/p>\n    <p><strong>Explanation: <\/strong>\n        Buy on day 1 (price = 1) and sell on day 5 (price = 5), profit = 5-1 = 4.\n        Total profit is 4.  \n    <\/p>\n\n    <h3>Example 3:<\/h3>\n    <p><strong>Input: <\/strong>prices = [7,6,4,3,1]<\/p>\n    <p><strong>Output: <\/strong>0<\/p>\n    <p><strong>Explanation: <\/strong>\n        There is no way to make a positive profit, so we never buy the stock to achieve the maximum profit of 0.\n    <\/p>\n\n    <h3>Constraints<\/h3>\n    <ul>\n        <li><code>1 <= prices.length <= 3 * 10<sup>4<\/sup><\/code><\/li>\n        <li><code>0 <= prices[i] <= 10<sup>4<\/sup><\/code><\/li>\n    <\/ul>\n<h2>Approach:<\/h2>\n    <ul>\n        <li>If the price today is higher than yesterday, we add the profit <code>(prices[i] - prices[i-1])<\/code> to our <strong>total<\/strong>.<\/li>\n        <li>Otherwise, we skip (no loss is counted). This way, we<strong> sum all upward moves to get the maximum profit.<\/strong><\/li>\n    <\/ul>\n\n    <h2>Time &#038; Space Complexity:<\/h2>\n    <p><strong>Time Complexity:<\/strong> <code>O(n)<\/code><\/p>\n    <p><strong>Space Complexity:<\/strong> <code>O(1)<\/code><\/p>\n\n<h2>Dry Run<\/h2> <div style=\"background: var(--light-bg); border-left: 4px solid var(--primary); padding: 1rem; border-radius: var(--tab-radius); margin: 1rem 0; color: var(--text-dark);\"> <p><strong>Input:<\/strong> <code>prices = [7, 1, 5, 3, 6, 4]<\/code><\/p> <pre style=\"white-space: pre-wrap; background: var(--code-bg); padding: 1rem; border-radius: 8px; overflow-x: auto; color: var(--code-text);\"> Step 1: Initialize ans = 0 Step 2: Iterate over prices i = 1 \u2192 profit = prices[1] - prices[0] = 1 - 7 = -6 profit \u2264 0 \u2192 no change \u2192 ans = 0 i = 2 \u2192 profit = prices[2] - prices[1] = 5 - 1 = 4 profit > 0 \u2192 ans = 0 + 4 = 4 i = 3 \u2192 profit = prices[3] - prices[2] = 3 - 5 = -2 profit \u2264 0 \u2192 no change \u2192 ans = 4 i = 4 \u2192 profit = prices[4] - prices[3] = 6 - 3 = 3 profit > 0 \u2192 ans = 4 + 3 = 7 i = 5 \u2192 profit = prices[5] - prices[4] = 4 - 6 = -2 profit \u2264 0 \u2192 no change \u2192 ans = 7 Step 3: End Return ans = 7 <\/pre> <p><strong>Output:<\/strong> <code>Result: 7<\/code><\/p> <\/div>\n<\/div>\n\n  <div class=\"wp_blog_code-tabs-container\">\n    <div class=\"wp_blog_code-tabs-header\">\n      <button class=\"wp_blog_code-tab-button active\" data-lang=\"js\">JavaScript<\/button>\n      <button class=\"wp_blog_code-tab-button\" data-lang=\"py\">Python<\/button>\n      <button class=\"wp_blog_code-tab-button\" data-lang=\"java\">Java<\/button>\n      <button class=\"wp_blog_code-tab-button\" data-lang=\"cpp\">C++<\/button>\n      <button class=\"wp_blog_code-tab-button\" data-lang=\"c\">C<\/button>\n      <button class=\"wp_blog_code-tab-button\" data-lang=\"cs\">C#<\/button>\n    <\/div>\n\n    <div class=\"wp_blog_code-tab-content active\" data-lang=\"js\">\n      <pre><code class=\"language-javascript\">\nvar maxProfit = function(prices) {\n    let ans = 0;\n    for(let i=1; i<prices.length; i++){\n        let profit = prices[i] - prices[i-1];\n        if(profit > 0){\n            ans += profit;\n        }\n    }\n    return ans;\n};\n<\/code><\/pre>\n    <\/div>\n\n    <div class=\"wp_blog_code-tab-content\" data-lang=\"py\">\n      <pre><code class=\"language-python\">\ndef maxProfit(prices):\n    ans = 0\n    for i in range(1, len(prices)):\n        profit = prices[i] - prices[i - 1]\n        if profit > 0:\n            ans += profit\n    return ans\n      <\/code><\/pre>\n    <\/div>\n\n    <div class=\"wp_blog_code-tab-content\" data-lang=\"java\">\n      <pre><code class=\"language-java\">\nclass Solution {\n    public int maxProfit(int[] prices) {\n        int ans = 0;\n        for (int i = 1; i < prices.length; i++) {\n            int profit = prices[i] - prices[i - 1];\n            if (profit > 0) {\n                ans += profit;\n            }\n        }\n        return ans;\n    }\n}\n    <\/code><\/pre>\n    <\/div>\n\n    <div class=\"wp_blog_code-tab-content\" data-lang=\"cpp\">\n      <pre><code class=\"language-cpp\">\n#include &lt;vector&gt;\nusing namespace std;\nclass Solution {\npublic:\n    int maxProfit(vector<int>& prices) {\n        int ans = 0;\n        for (int i = 1; i < prices.size(); i++) {\n            int profit = prices[i] - prices[i - 1];\n            if (profit > 0) {\n                ans += profit;\n            }\n        }\n        return ans;\n    }\n};\n<\/code><\/pre>\n    <\/div>\n    <div class=\"wp_blog_code-tab-content\" data-lang=\"c\">\n      <pre><code class=\"language-c\">\n#include &lt;stdbool.h&gt;\nint maxProfit(int* prices, int pricesSize) {\n    int ans = 0;\n    for (int i = 1; i < pricesSize; i++) {\n        int profit = prices[i] - prices[i - 1];\n        if (profit > 0) {\n            ans += profit;\n        }\n    }\n    return ans;\n}\n    <\/code><\/pre>\n    <\/div>\n\n    <div class=\"wp_blog_code-tab-content\" data-lang=\"cs\">\n      <pre><code class=\"language-csharp\">\npublic class Solution {\n    public int MaxProfit(int[] prices) {\n        int ans = 0;\n        for (int i = 1; i < prices.Length; i++) {\n            int profit = prices[i] - prices[i - 1];\n            if (profit > 0) {\n                ans += profit;\n            }\n        }\n        return ans;\n    }\n}\n      <\/code><\/pre>\n    <\/div>\n  <\/div>\n<\/div>\n\n<script>\ndocument.addEventListener(\"DOMContentLoaded\", () => {\n  const buttons = document.querySelectorAll(\".wp_blog_code-tab-button\");\n  const contents = document.querySelectorAll(\".wp_blog_code-tab-content\");\n\n  buttons.forEach((button) => {\n    button.addEventListener(\"click\", () => {\n      const lang = button.getAttribute(\"data-lang\");\n\n      buttons.forEach((btn) => btn.classList.remove(\"active\"));\n      contents.forEach((content) => content.classList.remove(\"active\"));\n\n      button.classList.add(\"active\");\n      document\n        .querySelector(`.wp_blog_code-tab-content[data-lang=\"${lang}\"]`)\n        .classList.add(\"active\");\n    });\n  });\n\n  const themeToggle = document.getElementById(\"blogNotesThemeToggle\");\n  const themeContainer = document.querySelector(\".wp_blog_theme\");\n\n  themeToggle.addEventListener(\"click\", () => {\n    themeContainer.classList.toggle(\"dark-mode\");\n    themeToggle.textContent =\n      themeContainer.classList.contains(\"dark-mode\") ? \"\u2600\ufe0f\" : \"\ud83c\udf19\";\n  });\n});\n<\/script>\n\n","protected":false},"excerpt":{"rendered":"<p>\ud83c\udf19 Problem Statement: You are given an integer array prices where prices[i] is the price of a given stock on the ith day. On each day, you may decide to buy and\/or sell the stock. You can only hold at most one share of the stock at any time. However, you can buy it then<\/p>\n","protected":false},"author":108,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[210,260,176,175,211,810,174,172,173],"tags":[],"class_list":["post-10068","post","type-post","status-publish","format-standard","category-algorithms","category-c-c-plus-plus","category-csharp","category-cplusplus","category-data-structures","category-dsa","category-java","category-javascript","category-python"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/10068","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/users\/108"}],"replies":[{"embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/comments?post=10068"}],"version-history":[{"count":2,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/10068\/revisions"}],"predecessor-version":[{"id":10070,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/10068\/revisions\/10070"}],"wp:attachment":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/media?parent=10068"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/categories?post=10068"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/tags?post=10068"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}