CPP Numeric Data Types

💻 C++ Numeric Data Types – Complete Beginner to Interview Guide

Numeric data types in C++ are used to store numbers.
They are mainly divided into Integer types and Floating-point types.

1️⃣ What are Numeric Data Types? ⭐

Numeric data types store numerical values that can be used in:

• calculations

• conditions

• loops

• mathematical operations

2️⃣ Categories of Numeric Data Types ⭐⭐

✅ 1. Integer Types (Whole Numbers)

✅ 2. Floating-Point Types (Decimal Numbers)

3️⃣ Integer Numeric Data Types ⭐⭐⭐

Used to store whole numbers (no decimals).

🔹 int

📌 Size: 4 bytes
📌 Range: approx -2,147,483,648 to 2,147,483,647

🔹 short int

📌 Size: 2 bytes

🔹 long int

📌 Size: 4 or 8 bytes (system dependent)

🔹 long long int

📌 Size: 8 bytes

🔹 unsigned int

📌 Stores only positive numbers
📌 Doubles positive range

4️⃣ Floating-Point Numeric Data Types ⭐⭐⭐

Used to store decimal values.

🔹 float

📌 Size: 4 bytes
📌 Precision: ~6–7 digits

🔹 double

📌 Size: 8 bytes
📌 Precision: ~15 digits

🔹 long double

📌 Size: 8, 12, or 16 bytes (compiler dependent)

5️⃣ Example Program (Numeric Data Types) ⭐⭐

Output

6️⃣ Size of Numeric Data Types ⭐⭐

📌 Size may vary based on system/compiler.

7️⃣ Integer vs Floating-Point ⚠️

Output

📌 Integer division removes decimals.

✔ Correct way:

Output:

8️⃣ Common Numeric Data Type Errors ❌

❌ Integer overflow
❌ Using int for decimal values
❌ Precision loss with float
❌ Assuming fixed size on all systems

📌 Interview Questions (Numeric Data Types)

Q1. Difference between int and float?
👉 int stores whole numbers, float stores decimals

Q2. Which data type has more precision: float or double?
👉 double

Q3. What is unsigned int?
👉 Stores only positive integers

✅ Summary

✔ Numeric data types store numbers
✔ Integer types → whole numbers
✔ Floating-point types → decimals
✔ Choose correct type for accuracy
✔ Important for exams & interviews