Function Templates and Class Templates

Advanced13 min read•Updated: 2026-10-22

🧬 Function Templates and Class Templates

Introduction

Templates enable generic programming: writing code once that works across any data type (integers, strings, custom classes) with zero runtime performance cost. During compilation, the compiler generates type-specific concrete instances through template instantiation.

🧮 Function Templates

1#include <iostream>
2#include <string>
3 
4// Generic Maximum Function
5template <typename T>
6T findMax(T a, T b) {
7    return (a > b) ? a : b;
8}
9 
10int main() {
11    std::cout << "Max int:    " << findMax(10, 25) << "\n";         // Instantiates findMax<int>
12    std::cout << "Max double: " << findMax(3.14, 2.71) << "\n";     // Instantiates findMax<double>
13    std::cout << "Max string: " << findMax(std::string("Alpha"), std::string("Zeta")) << "\n";
14    return 0;
15}

📦 Class Templates

1#include <iostream>
2#include <stdexcept>
3#include <array>
4 
5template <typename T, std::size_t Capacity>
6class StaticStack {
7private:
8    std::array<T, Capacity> m_elements;
9    std::size_t m_topIndex = 0;
10 
11public:
12    void push(const T& item) {
13        if (m_topIndex >= Capacity) throw std::overflow_error("Stack full!");
14        m_elements[m_topIndex++] = item;
15    }
16 
17    T pop() {
18        if (m_topIndex == 0) throw std::underflow_error("Stack empty!");
19        return m_elements[--m_topIndex];
20    }
21 
22    std::size_t size() const { return m_topIndex; }
23};
24 
25int main() {
26    StaticStack<int, 5> intStack;
27    intStack.push(10);
28    intStack.push(20);
29    std::cout << "Popped: " << intStack.pop() << "\n";
30 
31    StaticStack<std::string, 3> strStack;
32    strStack.push("MSK Institute");
33    std::cout << "String stack size: " << strStack.size() << "\n";
34 
35    return 0;
36}

Next Lesson

Template Specialization (Full and Partial Specialization)

Continue learning with hands-on practice, examples, and exercises in the upcoming topic.

Related Lessons

Previous Lesson	Next Lesson
Custom Deleters for Smart Pointers (C APIs, File Handles)	Template Specialization (Full and Partial Specialization)

Practice Quiz

Test your understanding of this lesson with 1 questions. Each question has one correct answer.

Previous Next

PreviousPrevNext

MSK Institute • Shikohabad

Loading Page Content...

Preparing courses, live labs, and learning resources.सामग्री लोड हो रही है, कृपया प्रतीक्षा करें...

Connecting serverPlease wait...

💻 Practical Labs🚀 Free Demo📜 Verified Certificates

Template Specialization (Full and Partial Specialization)

Function Templates and Class Templates

Advanced13 min read•Updated: 2026-10-22

Study Materials

🧬 Function Templates and Class Templates

Introduction

🧮 Function Templates

1#include <iostream>
2#include <string>
3 
4// Generic Maximum Function
5template <typename T>
6T findMax(T a, T b) {
7    return (a > b) ? a : b;
8}
9 
10int main() {
11    std::cout << "Max int:    " << findMax(10, 25) << "\n";         // Instantiates findMax<int>
12    std::cout << "Max double: " << findMax(3.14, 2.71) << "\n";     // Instantiates findMax<double>
13    std::cout << "Max string: " << findMax(std::string("Alpha"), std::string("Zeta")) << "\n";
14    return 0;
15}

📦 Class Templates

1#include <iostream>
2#include <stdexcept>
3#include <array>
4 
5template <typename T, std::size_t Capacity>
6class StaticStack {
7private:
8    std::array<T, Capacity> m_elements;
9    std::size_t m_topIndex = 0;
10 
11public:
12    void push(const T& item) {
13        if (m_topIndex >= Capacity) throw std::overflow_error("Stack full!");
14        m_elements[m_topIndex++] = item;
15    }
16 
17    T pop() {
18        if (m_topIndex == 0) throw std::underflow_error("Stack empty!");
19        return m_elements[--m_topIndex];
20    }
21 
22    std::size_t size() const { return m_topIndex; }
23};
24 
25int main() {
26    StaticStack<int, 5> intStack;
27    intStack.push(10);
28    intStack.push(20);
29    std::cout << "Popped: " << intStack.pop() << "\n";
30 
31    StaticStack<std::string, 3> strStack;
32    strStack.push("MSK Institute");
33    std::cout << "String stack size: " << strStack.size() << "\n";
34 
35    return 0;
36}

Next Lesson

Template Specialization (Full and Partial Specialization)

Continue learning with hands-on practice, examples, and exercises in the upcoming topic.

Related Lessons

Previous Lesson	Next Lesson
Custom Deleters for Smart Pointers (C APIs, File Handles)	Template Specialization (Full and Partial Specialization)

Practice Quiz

Test your understanding of this lesson with 1 questions. Each question has one correct answer.

Previous Next