Segmentation fault in vscode c++ - c++

Question

I am writing a simple program of linear search on vscode on macOS.
The code is producing an error called segmentation fault only in vscode.
But the strange thing is that code is working perfectly fine on onlinegdb compiler and Xcode IDE.
I have the default c++ compiler installed on my Mac which came after installing Xcode.
#include<iostream>
using namespace std;
int linearSearch(int arr[], int n, int key){
int i = 0;
for(i = 0; i<n;i++)
{
if(arr[i] == key){
return i;
}
} return -1;
}
int main(){
int n = 0;
int arr[n];
int key = 0;
cout<<"Enter the length of the array"<<endl;
cin>>n;
cout<<"Enter the elements of the array"<<endl;
int i = 0;
for(i = 0; i<n;i++)
{
cin>>arr[i];
}
cout<<"Enter the element to search in array"<<endl;
cin>>key;
cout<<linearSearch(arr, n, key);
}[screenshot of the error in vscode][1]
[1]: https://i.stack.imgur.com/Bo3Nu.png

Answer 1

Segmentation fault isn't a vscode error, its a program error, it indicates that your program is accessing a memory adress that it hasn't reserved, thus the OS kills your program to save the system from wrong or bad memory accesses.
You first initialize n with 0 and then initialize the array arr with n ints. So it makes you an array with 0 ints. If you want to make this work, push the int arr[n] below the cin >> n. You will have to convert it first from a string to a int using stoi()
libraries:
#include <string>
#include <iostream>
code:
//Create the int to store the length of the array
int n = 0;
//A string, beacause cin returns a string
std::string s;
//Get the number
std::cout << "Length of array: ";
std::cin >> s;
//Convert the string to an int
n = stoi(s);
//Create the array
int arr[n];