- The basic data types that are predefined by the language. These types represent the simplest form of data and are not objects or classes. They are used to store simple values like numbers, characters, and booleans. Primitive types have a fixed size in memory, making them efficient for storage and processing.
- Stores whole numbers
- Size -> 4 bytes (32 bits)
- Range -> -231 to 231 - 1
- Example
#include <iostream> using namespace std; int main() { int x = 10; int y = -5; cout << "x = " << x << ", y = " << y << endl; return 0; }
| Float | Double |
|---|---|
| Size -> 4 bytes | Size -> 8 bytes |
| Precision -> Up to 7 decimal digits | Precision -> Up to 15-16 decimal digits |
- Example
#include <iostream> using namespace std; int main() { double x = 9.80665; cout << "x: " << x << endl; return 0; }
-
Store a Single Character
-
Size -> 1 byte
-
Range -> 0 to 255 in ASCII
-
ASCII
- The ASCII (American Standard Cod for Information Interchange)
Decimal Hex Character Description 0 00 NUL Null character 1 01 SOH Start of Heading 2 02 STX Start of Text 3 03 ETX End of Text 4 04 EOT End of Transmission 5 05 ENQ Enquiry 6 06 ACK Acknowledgment 7 07 BEL Bell 8 08 BS Backspace 9 09 TAB Horizontal Tab 10 0A LF Line Feed 11 0B VT Vertical Tab 12 0C FF Form Feed 13 0D CR Carriage Return 14 0E SO Shift Out 15 0F SI Shift In 16 10 DLE Data Link Escape 17 11 DC1 Device Control 1 18 12 DC2 Device Control 2 19 13 DC3 Device Control 3 20 14 DC4 Device Control 4 21 15 NAK Negative Acknowledgment 22 16 SYN Synchronize 23 17 ETB End of Transmission Block 24 18 CAN Cancel 25 19 EM End of Medium 26 1A SUB Substitute 27 1B ESC Escape 28 1C FS File Separator 29 1D GS Group Separator 30 1E RS Record Separator 31 1F US Unit Separator 32 20 (space) Space 33 21 ! Exclamation mark 34 22 " Double quotes 35 23 # Number sign 36 24 $ Dollar sign 37 25 % Percent sign 38 26 & Ampersand 39 27 ' Single quote 40 28 ( Left parenthesis 41 29 ) Right parenthesis 42 2A * Asterisk 43 2B + Plus sign 44 2C , Comma 45 2D - Hyphen 46 2E . Period 47 2F / Slash 48 30 0 Digit 0 49 31 1 Digit 1 50 32 2 Digit 2 51 33 3 Digit 3 52 34 4 Digit 4 53 35 5 Digit 5 54 36 6 Digit 6 55 37 7 Digit 7 56 38 8 Digit 8 57 39 9 Digit 9 58 3A : Colon 59 3B ; Semicolon 60 3C < Less than 61 3D = Equal sign 62 3E > Greater than 63 3F ? Question mark 64 40 @ At sign 65 41 A Uppercase A 66 42 B Uppercase B 67 43 C Uppercase C 68 44 D Uppercase D 69 45 E Uppercase E 70 46 F Uppercase F 71 47 G Uppercase G 72 48 H Uppercase H 73 49 I Uppercase I 74 4A J Uppercase J 75 4B K Uppercase K 76 4C L Uppercase L 77 4D M Uppercase M 78 4E N Uppercase N 79 4F O Uppercase O 80 50 P Uppercase P 81 51 Q Uppercase Q 82 52 R Uppercase R 83 53 S Uppercase S 84 54 T Uppercase T 85 55 U Uppercase U 86 56 V Uppercase V 87 57 W Uppercase W 88 58 X Uppercase X 89 59 Y Uppercase Y 90 5A Z Uppercase Z 91 5B [ Left bracket 92 5C \ Backslash 93 5D ] Right bracket 94 5E ^ Caret 95 5F _ Underscore 96 60 ` Grave accent 97 61 a Lowercase a 98 62 b Lowercase b 99 63 c Lowercase c 100 64 d Lowercase d 101 65 e Lowercase e 102 66 f Lowercase f 103 67 g Lowercase g 104 68 h Lowercase h 105 69 i Lowercase i 106 6A j Lowercase j 107 6B k Lowercase k 108 6C l Lowercase l 109 6D m Lowercase m 110 6E n Lowercase n 111 6F o Lowercase o 112 70 p Lowercase p 113 71 q Lowercase q 114 72 r Lowercase r 115 73 s Lowercase s 116 74 t Lowercase t 117 75 u Lowercase u 118 76 v Lowercase v 119 77 w Lowercase w 120 78 x Lowercase x 121 79 y Lowercase y 122 7A z Lowercase z 123 7B { Left brace 124 7C | Vertical bar 125 7D } Right brace 126 7E ~ Tilde 127 7F DEL Delete 128 80 Ç Capital C with cedilla 129 81 ü Small u with diaeresis 130 82 é Small e with acute 131 83 â Small a with circumflex 132 84 ä Small a with diaeresis 133 85 à Small a with grave 134 86 å Small a with ring 135 87 ç Small c with cedilla 136 88 ê Small e with circumflex 137 89 ë Small e with diaeresis 138 8A è Small e with grave 139 8B ï Small i with diaeresis 140 8C î Small i with circumflex 141 8D ì Small i with grave 142 8E Ä Capital A with diaeresis 143 8F Å Capital A with ring 144 90 É Capital E with acute 145 91 æ Lowercase ae 146 92 Æ Uppercase AE 147 93 ô Small o with circumflex 148 94 ö Small o with diaeresis 149 95 ò Small o with grave 150 96 û Small u with circumflex 151 97 ù Small u with grave 152 98 ÿ Small y with diaeresis 153 99 Ö Capital O with diaeresis 154 9A Ü Capital U with diaeresis 155 9B ø Small o with stroke 156 9C £ British Pound Sign 157 9D Ø Capital O with stroke 158 9E × Multiplication sign 159 9F ƒ Florin 160 A0 (non-breaking space) Non-breaking space 161 A1 ¡ Inverted exclamation mark 162 A2 ¢ Cent sign 163 A3 £ Pound sign 164 A4 ¥ Yen sign 165 A5 ¦ Broken bar 166 A6 § Section sign 167 A7 ¨ Diaeresis (two dots) 168 A8 © Copyright sign 169 A9 ® Registered sign 170 AA ¬ Not sign 171 AB ½ One-half 172 AC ¼ One-quarter 173 AD ¡ Inverted exclamation mark 174 AE ¾ Three-quarters 175 AF ¶ Pilcrow sign 176 B0 • Bullet 177 B1 ¨ Diaeresis 178 B2 ¹ Superscript one 179 B3 ² Superscript two 180 B4 ³ Superscript three 181 B5 ´ Acute accent 182 B6 µ Micro sign 183 B7 ¶ Pilcrow sign 184 B8 · Middle dot 185 B9 ¹ Superscript one 186 BA º Masculine ordinal indicator 187 BB » Right angle quotation mark 188 BC ¼ One-quarter 189 BD ½ One-half 190 BE ¾ Three-quarters 191 BF ¿ Inverted question mark 192 C0 À Capital A with grave 193 C1 Á Capital A with acute 194 C2 Â Capital A with circumflex 195 C3 Ã Capital A with tilde 196 C4 Ä Capital A with diaeresis 197 C5 Å Capital A with ring 198 C6 Æ Capital AE 199 C7 Ç Capital C with cedilla 200 C8 È Capital E with grave 201 C9 É Capital E with acute 202 CA Ê Capital E with circumflex 203 CB Ë Capital E with diaeresis 204 CC Ì Capital I with grave 205 CD Í Capital I with acute 206 CE Î Capital I with circumflex 207 CF Ï Capital I with diaeresis 208 D0 Ð Capital Eth (Icelandic) 209 D1 Ñ Capital N with tilde 210 D2 Ò Capital O with grave 211 D3 Ó Capital O with acute 212 D4 Ô Capital O with circumflex 213 D5 Õ Capital O with tilde 214 D6 Ö Capital O with diaeresis 215 D7 × Multiplication sign 216 D8 Ø Capital O with stroke 217 D9 Ù Capital U with grave 218 DA Ú Capital U with acute 219 DB Û Capital U with circumflex 220 DC Ü Capital U with diaeresis 221 DD Ý Capital Y with acute 222 DE Þ Capital Thorn (Icelandic) 223 DF ß Small sharp s 224 E0 à Small a with grave 225 E1 á Small a with acute 226 E2 â Small a with circumflex 227 E3 ã Small a with tilde 228 E4 ä Small a with diaeresis 229 E5 å Small a with ring 230 E6 æ Lowercase ae 231 E7 ç Small c with cedilla 232 E8 è Small e with grave 233 E9 é Small e with acute 234 EA ê Small e with circumflex 235 EB ë Small e with diaeresis 236 EC ì Small i with grave 237 ED í Small i with acute 238 EE î Small i with circumflex 239 EF ï Small i with diaeresis 240 F0 ð Small eth (Icelandic) 241 F1 ñ Small n with tilde 242 F2 ò Small o with grave 243 F3 ó Small o with acute 244 F4 ô Small o with circumflex 245 F5 õ Small o with tilde 246 F6 ö Small o with diaeresis 247 F7 ÷ Division sign 248 F8 ø Small o with stroke 249 F9 ù Small u with grave 250 FA ú Small u with acute 251 FB û Small u with circumflex 252 FC ü Small u with diaeresis 253 FD ý Small y with acute 254 FE þ Small thorn (Icelandic) 255 FF ÿ Small y with diaeresis - Each character corresponds to a unique decimal and hexadecimal value.
- You can convert characters to their numeric representations and vice versa using this table.
- Commonly used in programming, data transmission, and other computing applications to ensure that systems can interpret and manipulate text consistently.
You can easily print the ASCII value of a character in C++:
#include <iostream> using namespace std; int main() { char ch = 'A'; cout << "ASCII value of " << ch << " is " << int(ch) << endl; return 0; }
- This program will output:
ASCII value of A is 65.
- Store True or False
- Size 1 byte
- Example
#include <iostream> using namespace std; int main() { bool isPassed = true; cout << "Passed the exam: " << isPassed << endl; // Outputs 1 for true return 0; }
- Conditional statements allow a program to make decisions.
- if-else
- Example
if (condition) { // code when condition is true } else { // code when condition is false }
- Example
- Loops are used to repeat code.
- For Loop: Repeats code a specific number of times.
- Example
for (int i = 0; i < 5; i++) { // code to be repeated }
- while loop: Repeats code as long as a condition is true.
- Example
while (condition) { // code to be repeated }
- do-while loop:Same as while, but ensures code runs at least once
- Example
do { // code to be repeated } while (condition);
-
An array is a data structure that stores a fixed-size sequential collection of elements of the same type. Arrays are used to store multiple values in a single variable, making it easier to manage collections of data.
-
Fixed Size: The size of an array is defined at the time of declaration and cannot be changed during runtime.
-
Homogeneous Elements: All elements in an array are of the same type (e.g., all integers, all floats, etc.).
-
Indexed Access: Elements in an array can be accessed using their index, which usually starts from
0. -
Example
- Consider an array that stores the first five positive integers:
Index: 0 1 2 3 4 | | | | | Array: [ 1, 2, 3, 4, 5 ]
You can access individual elements in an array using their index:
array[0]→1array[1]→2array[2]→3array[3]→4array[4]→5
#include <iostream> using namespace std; int main() { int array[5] = {1, 2, 3, 4, 5}; // Declare an array of integers // Accessing and printing array elements for (int i = 0; i < 5; i++) { cout << "Element at index " << i << ": " << array[i] << endl; } return 0; }
- Consider an array that stores the first five positive integers:
- A single row of elements.
-
A 2D array (two-dimensional array) is an array of arrays.
It is a data structure that can be used to represent a matrix or a table with rows and columns.
Each element in a 2D array is accessed using two indices: one for the row and one for the column. -
Rectangular Structure: A 2D array consists of rows and columns, making it suitable for representing grid-like structures.
-
Fixed Size: Like regular arrays, the size of a 2D array is defined at the time of declaration and cannot be changed during runtime.
-
Homogeneous Elements: All elements in a 2D array are of the same type (e.g., all integers, all floats, etc.).
-
Indexed Access: Elements can be accessed using their row and column indices.
Consider a 2D array that represents a 3x3 matrix:
Column 0 1 2 +---+---+---+ Row 0 | 1 | 2 | 3 | +---+---+---+ Row 1 | 4 | 5 | 6 | +---+---+---+ Row 2 | 7 | 8 | 9 | +---+---+---+You can access individual elements in a 2D array using their row and column indices:
array[0][0]→1array[1][2]→6array[2][1]→8
Here’s an example of how to declare and use a 2D array in C++:
#include <iostream> using namespace std; int main() { int array[3][3] = { {1, 2, 3}, {4, 5, 6}, {7, 8, 9} }; // Declare a 3x3 2D array // Accessing and printing array elements for (int i = 0; i < 3; i++) { for (int j = 0; j < 3; j++) { cout << "Element at [" << i << "][" << j << "]: " << array[i][j] << endl; } } return 0; }