Passing Array to a Function in C++ Programming

Passing Array to a Function in C++ Programming

In this tutorial, we will learn how to pass a single-dimensional and multidimensional array as a capacity parameter in C++ with the help of examples.

In C++, we can pass arrays as a contention to a capacity. What’s more, additionally we can return arrays from a capacity.

Before you find out about passing arrays as a function contention, ensure you think about C++ Arrays and C++ Functions.

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The syntax for Passing Arrays as Function Parameters

The syntax for passing an array to a function is

returnType functionName(dataType arrayName[arraySize]) {
    // code
}

Let’s see an example,

int total(int marks[5]) {
    // code
}

Here, we have passed an int type array named marks to the function total(). The size of the array is 5.

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Example 1: Passing One-dimensional Array to a Function

// C++ Program to display marks of 5 students

#include <iostream>
using namespace std;

// declare function to display marks
// take a 1d array as parameter
void display(int m[5]) {
    cout << "Displaying marks: " << endl;

    // display array elements    
    for (int i = 0; i < 5; ++i) {
        cout << "Student " << i + 1 << ": " << m[i] << endl;
    }
}

int main() {

    // declare and initialize an array
    int marks[5] = {88, 76, 90, 61, 69};
    
    // call display function
    // pass array as argument
    display(marks);

    return 0;
}

Output

Displaying marks: 
Student 1: 88
Student 2: 76
Student 3: 90
Student 4: 61
Student 5: 69

Here,

1. When we call a function by passing an array as the argument, only the name of the array is used.

display(marks);

Here, the argument marks represent the memory address of the first element of array marks[5].

2. However, notice the parameter of the display() function.

void display(int m[5])

Here, we use the full statement of the exhibit in the capacity parameter, including the square braces [].

3.

The function parameter int m[5] changes over to int* m;. This focuses to a similar location pointed by the array marks. This implies when we control m[5] in the capacity body, we are really controlling the first array marks.

C++ handles passing an array to a capacity thusly to spare memory and time.

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Passing Multidimensional Array to a Function

We can also pass Multidimensional arrays as an argument to the function. For example,

Example 2: Passing Multidimensional Array to a Function

// C++ Program to display the elements of two
// dimensional array by passing it to a function

#include <iostream>
using namespace std;

// define a function 
// pass a 2d array as a parameter
void display(int n[][2]) {
    cout << "Displaying Values: " << endl;
    for (int i = 0; i < 3; ++i) {
        for (int j = 0; j < 2; ++j) {
            cout << "num[" << i << "][" << j << "]: " << n[i][j] << endl;
        }
    }
}

int main() {

    // initialize 2d array
    int num[3][2] = {
        {3, 4},
        {9, 5},
        {7, 1}
    };

    // call the function
    // pass a 2d array as an argument
    display(num);

    return 0;
}

Output

Displaying Values: 
num[0][0]: 3
num[0][1]: 4
num[1][0]: 9
num[1][1]: 5
num[2][0]: 7
num[2][1]: 1

In the above program, we have characterized a capacity named display(). The function takes a two-dimensional array, int n[][2] as its contention, and prints the components of the array.

While calling the capacity, we just pass the name of the two-dimensional cluster as the capacity contention display(num).

Note: It isn’t obligatory to indicate the number of lines in the cluster. In any case, the number of sections ought to consistently be indicated. This is the reason we have used int n[][2].

We can likewise pass arrays with multiple measurements as a capacity contention.

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C++ Returning an Array From a Function

We can likewise return an array from the capacity. However, the actual array isn’t returned. Rather the location of the first component of the array comes back with the help of pointers.

We will find out about returning arrays from a function in the coming tutorials.

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Please feel free to give your comment if you face any difficulty here.

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