How to create a distance matrix using the HC-SR04 sensor?

Arduino

void setup() {

  float cd = 1.0;
  float arrBuff[10];
  for (int i =0; i<10;++i)
  {
    arrBuff[i] =cd+3.45;
    cd++;
  }
  
  Serial.begin(9600);
 for(int i=0; i<10; ++i)
 {
   Serial.println(arrBuff[i]);
 }
  
}


void loop() {
  
  

}

And for the main CPP:

#include "includes/serial/serial.hpp"
#include <iostream>
#include <stdio.h>
#include <string>
#include <vector>

const char* portName = "\\\\.\\COM3";

#define MAX_DATA_LEN sizeof(float)

char incomingData[MAX_DATA_LEN];


SerialPort* arduino;


void  exampleReceiveData(void)
{
	float readResult = (float)arduino->readPort(incomingData, MAX_DATA_LENGTH);
	printf("%.2f\n", readResult);
	Sleep(1000);
}

void autoConnect()
{
	while (1)
	{
		std::cout << "search in progress" << std::endl;

		while (!arduino->isConnected())
		{
			Sleep(1);
			std::cout << " \b\\" << std::flush;
			Sleep(1);
			std::cout << "\b|" << std::flush;
			Sleep(1);
			std::cout << "\b/" << std::flush;
			Sleep(1);
			std::cout << "\b-" << std::flush;

			arduino = new SerialPort(portName);
		}
		if (arduino->isConnected())
		{
			std::cout << "Connectd to port: " << portName << std::endl;
		}
		while (arduino->isConnected())
		{
			exampleReceiveData();
		}

	}
}


int main()
{
	arduino = new SerialPort(portName);
	autoConnect();
	return 0;
}

rest of the code is from the Github link:
https://github.com/manashmandal/SerialPort