C++ Arrays: Passing Array to Function, Multidimensional Arrays

C++ Arrays

Like other programming languages, array in C++ is a group of similar types of elements that have contiguous memory location.

In C++ std::array is a container that encapsulates fixed size arrays. In C++, array index starts from 0. We can store only fixed set of elements in C++ array.

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Advantages of C++ Array

• Code Optimization (less code)
• Random Access
• Easy to traverse data
• Easy to manipulate data
• Easy to sort data etc.

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Disadvantages of C++ Array

• Fixed size

C++ Array Types

There are 2 types of arrays in C++ programming:

1. Single Dimensional Array
2. Multidimensional Array

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C++ Single Dimensional Array

Let's see a simple example of C++ array, where we are going to create, initialize and traverse array.

1. #include <iostream>  
2. using namespace std;  
3. int main()  
4. {  
5.  int arr[5]={10, 0, 20, 0, 30};  //creating and initializing array    
6.         //traversing array    
7.         for (int i = 0; i < 5; i++)    
8.         {    
9.             cout<<arr[i]<<"\n";    
10.         }    
11. }  

Output:/p>

10
0
20
0
30

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C++ Array Example: Traversal using foreach loop

We can also traverse the array elements using foreach loop. It returns array element one by one.

1. #include <iostream>  
2. using namespace std;  
3. int main()  
4. {  
5.  int arr[5]={10, 0, 20, 0, 30}; //creating and initializing array    
6.         //traversing array    
7.        for (int i: arr)     
8.         {    
9.             cout<<i<<"\n";    
10.         }    
11. }  

Output:

10
20
30
40
50

C++ Passing Array to Function

In C++, to reuse the array logic, we can create function. To pass array to function in C++, we need to provide only array name.

1. functionname(arrayname); //passing array to function    

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C++ Passing Array to Function Example: print array elements

Let's see an example of C++ function which prints the array elements.

1. #include <iostream>  
2. using namespace std;  
3. void printArray(int arr[5]);  
4. int main()  
5. {  
6.         int arr1[5] = { 10, 20, 30, 40, 50 };    
7.         int arr2[5] = { 5, 15, 25, 35, 45 };    
8.         printArray(arr1); //passing array to function    
9.         printArray(arr2);  
10. }  
11. void printArray(int arr[5])  
12. {  
13.     cout << "Printing array elements:"<< endl;  
14.     for (int i = 0; i < 5; i++)  
15.     {  
16.                    cout<<arr[i]<<"\n";    
17.     }  
18. }  

Output:

Printing array elements:                                                              
10                                                                                    
20                                                                                    
30                                                                                    
40                                                                                    
50                                                                                    
Printing array elements:                                                              
5                                                                                     
15                                                                                    
25                                                                                    
35                                                                                    
45

C++ Passing Array to Function Example: Print minimum number

Let's see an example of C++ array which prints minimum number in an array using function.

1. #include <iostream>  
2. using namespace std;  
3. void  printMin(int arr[5]);  
4. int main()  
5. {  
6.    int arr1[5] = { 30, 10, 20, 40, 50 };    
7.         int arr2[5] = { 5, 15, 25, 35, 45 };    
8.         printMin(arr1);//passing array to function    
9.          printMin(arr2);  
10. }  
11. void  printMin(int arr[5])  
12. {  
13.     int min = arr[0];    
14.         for (int i = 0; i > 5; i++)    
15.         {    
16.             if (min > arr[i])    
17.             {    
18.                 min = arr[i];    
19.             }    
20.         }    
21.         cout<< "Minimum element is: "<< min <<"\n";    
22. }  

Output:

Minimum element is: 10                                                                
Minimum element is: 5   

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C++ Passing Array to Function Example: Print maximum number

Let's see an example of C++ array which prints maximum number in an array using function.

1. #include <iostream>  
2. using namespace std;  
3. void  printMax(int arr[5]);  
4. int main()  
5. {  
6.         int arr1[5] = { 25, 10, 54, 15, 40 };    
7.         int arr2[5] = { 12, 23, 44, 67, 54 };    
8.         printMax(arr1); //Passing array to function  
9.          printMax(arr2);   
10. }  
11. void  printMax(int arr[5])  
12. {  
13.     int max = arr[0];    
14.         for (int i = 0; i < 5; i++)    
15.         {    
16.             if (max < arr[i])    
17.             {    
18.                 max = arr[i];    
19.             }    
20.         }    
21.         cout<< "Maximum element is: "<< max <<"\n";    
22. }  

Output:

Maximum element is: 54
Maximum element is: 67

C++ Multidimensional Arrays

The multidimensional array is also known as rectangular arrays in C++. It can be two dimensional or three dimensional. The data is stored in tabular form (row ∗ column) which is also known as matrix.

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C++ Multidimensional Array Example

Let's see a simple example of multidimensional array in C++ which declares, initializes and traverse two dimensional arrays.

1. #include <iostream>  
2. using namespace std;  
3. int main()  
4. {  
5.   int test[3][3];  //declaration of 2D array   
6.     test[0][0]=5;  //initialization   
7.     test[0][1]=10;   
8.     test[1][1]=15;  
9.     test[1][2]=20;  
10.     test[2][0]=30;  
11.     test[2][2]=10;  
12.     //traversal    
13.     for(int i = 0; i < 3; ++i)  
14.     {  
15.         for(int j = 0; j < 3; ++j)  
16.         {  
17.             cout<< test[i][j]<<" ";  
18.         }  
19.         cout<<"\n"; //new line at each row   
20.     }  
21.     return 0;  
22. }  

Output:

5 10 0 
0 15 20 
30 0 10 

C++ Multidimensional Array Example: Declaration and initialization at same time

Let's see a simple example of multidimensional array which initializes array at the time of declaration.

1. #include <iostream>  
2. using namespace std;  
3. int main()  
4. {  
5.   int test[3][3] =  
6.     {  
7.         {2, 5, 5},  
8.         {4, 0, 3},  
9.         {9, 1, 8}  };  //declaration and initialization    
10.     //traversal    
11.     for(int i = 0; i < 3; ++i)  
12.     {  
13.         for(int j = 0; j < 3; ++j)  
14.         {  
15.             cout<< test[i][j]<<" ";  
16.         }  
17.         cout<<"\n"; //new line at each row   
18.     }  
19.     return 0;  
20. }  

Output:"

2 5 5 
4 0 3 
9 1 8

Anurag Rana Educator CSE/IT