get Top Manager in Salesforce Apex.

getTopManager

public Employee__c getTopManager(String employeeId){

    Boolean topLevel = false;
   
    Employee__c top_employee = new Employee__c();
    
    
    while(!topLevel){
        Employee__c employee = [Select Id,Name,Manager__c from Employee__c where Id =:employeeId limit 1];

        if(employee.Manager__c != null){           
            employeeId = employee.Manager__c;          
        }
        else{
            top_employee = employee;
            topLevel = true;
            System.debug('Manager: '+top_employee);
        }
    }
    return top_employee;
}