1. Arrays
Imran Rashid
CTO at ManiWeber Technologies

2. Outline What & Why One Dimensional Array Initializing Arrays Lab Work
2-D Arrays

3. What & Why

4. What & Why What is an array? Why we need arrays?
Array is a collection of data of same types stored in sequential memory location
It is a linear data structure, where data is stored sequentially one after the other
The elements in an array is accessed using an index
Why we need arrays?
In programming, one of the frequently arising problem is to handle numerous data of same type
Consider this situation, you are taking a survey of 100 people & you have to store their ages & to solve this you can create an integer array having 100 elements

5. One Dimensional Array

6. One Dimensional Array
An array in which data are arranged linearly in only one dimension is called one dimensional array
It is commonly known as 1-D array
Syntax/Example
datatype array_name[size];
int ages[5]; // declares an integer array with 5 elements
float arr[5]; // declares an float array with 5 elements
char n[50]; // declares an character array with 50 elements 1 2 3 4
ages[0]
ages[1]
ages[2]
ages[3]
ages[4]

7. Initializing Arrays

8. Initializing Arrays
You can initialize C++ array elements either one by one or using a single statement
int ages[5];
ages[0] = 10;
ages[1] = 20;
ages[2] = 30;
ages[3] = 40;
ages[4] = 50;
int ages[5] = {10, 20, 30, 40, 50};
float cgpas[5] = {3.5, 2.9, 2.0, 4.0, 3.8};
char vowels[5] = {‘a’, ‘o’, ‘i’, ‘e’, ‘u’};
double balance[3] = {1000.0, 2.0, 3.4}; 10 20 30 40 50
ages[0]
ages[1]
ages[2]
ages[3]
ages[4]

9. Lab Work

10. Lab Work
Write a C++ program to find the sum and average of one dimensional integer array?
Enter number of elements you want to insert 5 Enter element in ascending order Enter element 1: 8 Enter element 2: 1 Enter element 3: 10 Enter element 4: 5 Enter element 5: 6
The sum of Array is :30 The average of Array is :6

11. Lab Work
Solution

12. Lab Work
Write a C++ program to reverse the element of an integer 1-D array?
Enter number of elements you want to insert 6 Enter element 1: 13 Enter element 2: 69 Enter element 3: 30 Enter element 4: 51 Enter element 5: 11 Enter element 6: 81
Reverse array

13. Lab Work
Solution

14. Lab Work
Write a C++ program to find the largest and smallest element of an array?
Enter number of elements you want to insert 5 Enter element 1: 13 Enter element 2: 69 Enter element 3: 30 Enter element 4: 51 Enter element 5: 11
Largest element is : 69 Smallest element is : 11

15. Lab Work
Solution

16. 2-D Arrays

17. m[0][0] m[0][1] m[0][2] m[0][3] m[1][0] m[1][1] m[1][2] m[1][3]
2-D Arrays
In C++ programming, you can create an array of arrays known as multidimensional array
int m[3][4];
Column 01
[0]
Column 02
[1]
Column 03
[2]
Column 04
[3]
Row 01
m[0][0]
m[0][1]
m[0][2]
m[0][3]
Row 02
m[1][0]
m[1][1]
m[1][2]
m[1][3]
Row 03
m[2][0]
m[2][1]
m[2][2]
m[2][3]

18. 2-D Arrays
Initializing 2-D Arrays (guess the addresses)
int m[3][4] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12}};
Column 01
[0]
Column 02
[1]
Column 03
[2]
Column 04
[3]
Row 01 1 2 3 4
Row 02 5 6 7 8
Row 03 9 10 11 12

19. Quiz Consider the given 2-D array & convert rows to columns 1 2 3 4 56 7 8 9 1 4 7 2 5 8 3 6 9

20. Any ?