Randomly generate string with characters and numbers in C++

RandomString.cpp

#include <iostream>
#include <string>
#include <stdlib.h>
using namespace std;

string randomString()
{
	string str = "AAAAAA";
  
    // string sequence
	str[0] = rand() % 26 + 65;
	str[1] = rand() % 26 + 65;
	str[2] = rand() % 26 + 65;
	
    // number sequence
	str[3] = rand() % 10 + 48;
	str[4] = rand() % 10 + 48;
	str[5] = rand() % 10 + 48;

	return str;
}

int main() {
	
	cout << randomString();
	return 0;
}