Question

How to return pointer to array in C++

Answer 1

#include <iostream>

int *addToArray(int arr[], int size, int n) {
    for (int i = 0; i < size; i++) {
        arr[i] += n;
    }
    return arr;
}

int main() {
    int arr[] = {1, 2, 3, 4, 5};
    
    int size = sizeof(arr)/sizeof(arr[0]);

    int *p = addToArray(arr, size, 22);

    for (int i = 0; i < size; i++) {
        std::cout << p[i] << " ";
    }

    return 0;
}
    
    
    
    
/*
run:
  
23 24 25 26 27 
     
*/

 

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Answer 2

#include <iostream>
#include <array>

int *addToArray(int *arr, int size, int n) {
    for (int i = 0; i < size; i++) {
        arr[i] += n;
    }
    return arr;
}


int main() {
    std::array<int, 5> arr = {1, 2, 3, 4, 5};
    
    int *p = addToArray(arr.data(), arr.size(), 22);

    for (int i = 0; i < arr.size(); i++) {
        std::cout << p[i] << " ";
    }

    return 0;
}
    
    
    
    
/*
run:
  
23 24 25 26 27 
     
*/

 

Cleaner teeth, healthier you!
Get The Secret to a Bright and Healthy Smile

Answer 3

#include <iostream>
 
int *add(int a[], int size) {
    int *arr = new int[size];
    
    for (int i = 0; i < size; i++) 
        arr[i] = a[i] + 10;
    
    return arr;
}
 
int main() {
    int arr[] = {1, 2, 3, 4, 5};
     
    int size = sizeof(arr)/sizeof(arr[0]);
 
    int *p = add(arr, size);
 
    for (int i = 0; i < size; i++) {
        std::cout << p[i] << " ";
    }
    
    delete[] p;
 
    return 0;
}
     
     
     
     
/*
run:
   
11 12 13 14 15 
      
*/

 

Cleaner teeth, healthier you!
Get The Secret to a Bright and Healthy Smile