{"id":6746,"date":"2025-06-14T12:26:42","date_gmt":"2025-06-14T06:56:42","guid":{"rendered":"https:\/\/namastedev.com\/blog\/?p=6746"},"modified":"2025-10-22T10:48:48","modified_gmt":"2025-10-22T05:18:48","slug":"count-negative-numbers-in-an-array","status":"publish","type":"post","link":"https:\/\/namastedev.com\/blog\/count-negative-numbers-in-an-array\/","title":{"rendered":"Count Negative Numbers in an Array"},"content":{"rendered":"\n\n<link\n    href=\"https:\/\/cdn.jsdelivr.net\/npm\/prismjs@1.29.0\/themes\/prism-tomorrow.min.css\"\n    rel=\"stylesheet\"\n\/>\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; 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\/* 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    <div class=\"wp_blog_explanation\">\n        <h2>Problem Statement:<\/h2>\n        <p>Write a function that returns the number of negative numbers in an array.<\/p>\n        <h2>Approach:<\/h2>\n        <ul>\n            <li>Initialize a counter to 0.<\/li>\n            <li>Loop through the array.<\/li>\n            <li>If the element is less than 0, increment the counter.<\/li>\n            <li>Return the final count after the loop ends.<\/li>\n        <\/ul>\n\n        <h2>Example:<\/h2>\n        <p><strong>Input:<\/strong> arr = [2, -6, 4, 8, 1, -9]<\/p>\n        <p><strong>Output:<\/strong> 2<\/p>\n\n        <h2>Time &#038; Space Complexity:<\/h2>\n        <p><strong>Time Complexity:<\/strong> O(n) \u2014 where <strong>n<\/strong> is the number of elements in the array.<\/p>\n        <p><strong>Space Complexity:<\/strong> O(1) \u2014 Only a counter variable is used.<\/p>\n\n        <h2>Visualisation:<\/h2>\n        <img decoding=\"async\" src=\"https:\/\/namastedev.com\/blog\/wp-content\/uploads\/2025\/06\/Screenshot-2025-06-21-at-11.54.30\u202fAM.png\" alt=\"Visual representation of sum\" \/>\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        <!-- JavaScript -->\n        <div class=\"wp_blog_code-tab-content active\" data-lang=\"js\">\n            <pre><code class=\"language-javascript\">\nfunction countNegativeNumbers(arr) {\n  let count = 0;\n  for (let i = 0; i < arr.length; i++) {\n    if (arr[i] < 0) {\n      count++;\n    }\n  }\n  return count;\n}\nlet arr = [2, -6, 4, 8, 1, -9];\nlet result = countNegativeNumbers(arr);\nconsole.log(\"Result:\", result); \/\/ Output: 2\n            <\/code><\/pre>\n        <\/div>\n\n        <!-- Python -->\n        <div class=\"wp_blog_code-tab-content\" data-lang=\"py\">\n            <pre><code class=\"language-python\">\ndef count_negative_numbers(arr):\n    count = 0\n    for num in arr:\n        if num < 0:\n            count += 1\n    return count\n\narr = [2, -6, 4, 8, 1, -9]\nresult = count_negative_numbers(arr)\nprint(\"Result:\", result)  # Output: 2\n            <\/code><\/pre>\n        <\/div>\n\n        <!-- Java -->\n        <div class=\"wp_blog_code-tab-content\" data-lang=\"java\">\n            <pre><code class=\"language-java\">\npublic class Main {\n    public static int countNegativeNumbers(int[] arr) {\n        int count = 0;\n        for (int num : arr) {\n            if (num < 0) count++;\n        }\n        return count;\n    }\n    public static void main(String[] args) {\n        int[] arr = {2, -6, 4, 8, 1, -9};\n        int result = countNegativeNumbers(arr);\n        System.out.println(\"Result: \" + result); \/\/ Output: 2\n    }\n}\n            <\/code><\/pre>\n        <\/div>\n\n        <!-- C++ -->\n        <div class=\"wp_blog_code-tab-content\" data-lang=\"cpp\">\n            <pre><code class=\"language-cpp\">\n#include &lt;iostream&gt;\nusing namespace std;\n\nint countNegativeNumbers(int arr[], int n) {\n    int count = 0;\n    for (int i = 0; i < n; i++) {\n        if (arr[i] < 0) count++;\n    }\n    return count;\n}\n\nint main() {\n    int arr[] = {2, -6, 4, 8, 1, -9};\n    int result = countNegativeNumbers(arr, 6);\n    cout &lt;&lt; \"Result: \" &lt;&lt; result &lt;&lt; endl; \/\/ Output: 2\n    return 0;\n}\n            <\/code><\/pre>\n        <\/div>\n\n        <!-- C -->\n        <div class=\"wp_blog_code-tab-content\" data-lang=\"c\">\n            <pre><code class=\"language-c\">\n#include &lt;stdio.h&gt;\n\nint countNegativeNumbers(int arr[], int n) {\n    int count = 0;\n    for (int i = 0; i < n; i++) {\n        if (arr[i] < 0) count++;\n    }\n    return count;\n}\n\nint main() {\n    int arr[] = {2, -6, 4, 8, 1, -9};\n    int result = countNegativeNumbers(arr, 6);\n    printf(\"Result: %d\\n\", result); \/\/ Output: 2\n    return 0;\n}\n            <\/code><\/pre>\n        <\/div>\n\n        <!-- C# -->\n        <div class=\"wp_blog_code-tab-content\" data-lang=\"cs\">\n            <pre><code class=\"language-csharp\">\nusing System;\nclass Program\n{\n    static int CountNegativeNumbers(int[] arr)\n    {\n        int count = 0;\n        foreach (int num in arr)\n        {\n            if (num < 0)\n            {\n                count++;\n            }\n        }\n        return count;\n    }\n    static void Main()\n    {\n        int[] array = { 3, -1, 0, -4, 5, -6 };\n        int result = CountNegativeNumbers(array);\n        Console.WriteLine(\"Number of negative elements: \" + result);\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: Write a function that returns the number of negative numbers in an array. Approach: Initialize a counter to 0. Loop through the array. If the element is less than 0, increment the counter. Return the final count after the loop ends. Example: Input: arr = [2, -6, 4, 8, 1, -9] Output:<\/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":[322,260,176,175,211,811,174,173],"tags":[],"class_list":["post-6746","post","type-post","status-publish","format-standard","category-algorithms-and-data-structures","category-c-c-plus-plus","category-csharp","category-cplusplus","category-data-structures","category-data-structures-and-algorithms","category-java","category-python"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/6746","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=6746"}],"version-history":[{"count":11,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/6746\/revisions"}],"predecessor-version":[{"id":10521,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/6746\/revisions\/10521"}],"wp:attachment":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/media?parent=6746"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/categories?post=6746"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/tags?post=6746"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}