<script> function calc_num(obj1,obj2) { var itForm = document.forms[0]; var fr_num = obj1.value; var to_num = obj2.value; var c_count = 0; for(i=fr_num;i<=to_num;i++) { var ci =String(i); if(ci.indexOf("1") != -1) { var str = ci.split("1"); var str_length = str.length-1 c_count = c_count+str_length; } } itForm.calc.value = c_count; } </script> <form>시작숫자 ~ 끝나는숫자

1의 갯수 : </form>