function upper_case(str)  
    {  
       regexp = /^[A-Z]/;  
       if (regexp.test(str))  
        {  
          console.log("String's first character is uppercase");  
        }   
        else  
        {  
          console.log("String's first character is not uppercase");  
        }  
    }  
    upper_case('Abcd');  
    upper_case('abcd');