GDB won't let me output my code sometimes?

So, I'm new to C++. I need to learn this language quick for school. But I'm walking against some issues that make it difficult to work with this language. I downloaded visual studio code and followed the steps given by my school. But now I have the problem that sometimes my code just won't print.

Here is an example of a piece of code that does print (btw, I use a "makefile" to run all of this):

#include <iostream>int main(){    std::cout << "Hello world!" << std::endl;    return 0;}

Ofcourse, just a simple "hello world" but still, it does print. Now I'll give an example of a piece of code that won't print:

// C++ program to sort an// array using bucket sort#include <algorithm>#include <iostream>#include <vector>using namespace std;// Function to sort arr[] of// size n using bucket sortvoid bucketSort(float arr[], int n){    cout << "hello" << endl;    // 1) Create n empty buckets    vector<float> b[n];    // 2) Put array elements    // in different buckets    for (int i = 0; i < n; i++) {        int bi = n * arr[i]; // Index in bucket        b[bi].push_back(arr[i]);    }    // 3) Sort individual buckets    for (int i = 0; i < n; i++)        sort(b[i].begin(), b[i].end());    // 4) Concatenate all buckets into arr[]    int index = 0;    for (int i = 0; i < n; i++)        for (int j = 0; j < b[i].size(); j++)            arr[index++] = b[i][j];}/* Driver program to test above function */int main(){    cout << "hello" << endl;    float arr[]        = { 0.897, 0.565, 0.656, 0.1234, 0.665, 0.3434 };    int n = sizeof(arr) / sizeof(arr[0]);    bucketSort(arr, n);    cout << "Sorted array is \n";    for (int i = 0; i < n; i++)        cout << arr[i] << " ";    return 0;}

This is an example of a bucket sort I found online. First, the "n" on the vector<float> b[n] line, gave a red line, I chose the "ignore this error" option. Second, this code won't output anything. If I look into the "debug console" I find this error: ERROR: Unable to start debugging. Unexpected GDB output from command "-exec-run". During startup program exited with code 0xc0000139.

When I looked online I saw some people give the advice to downgrade my gdb version. I want to try that, but I can't find out how to do that haha. Can someone help me get my visual studio code working? This is the most irritating part of programming to me.