var shortMonths=new Array("Jan","Feb","Mar", "Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec");var longMonths=new Array("January","February","March","April","May","June","July","August","September","October","November","December" ); var leapDays=new Array(31,29,31,30,31,30,31,31,30,31,30,31);var yearDays=new Array(31,28,31,30,31,30,31,31,30,31,30,31);function isLeapYear(tYear) {return ((0 == (tYear%4)) && ((0 != (tYear%100)) || (0 == (tYear%400)))); } function isValidDayOfMonth(tDay,tMonth,tYear) { if (tDay<=0) {return false;}if (isLeapYear(tYear)) {return (tDay<=leapDays[tMonth-1]);}return (tDay<=yearDays[tMonth-1]); }function getDays(tMonth,tYear) {if (isLeapYear(tYear)) {return(leapDays[tMonth-1]);}return(yearDays[tMonth-1]);}function validate() {var tDay,tMonth,tYear;tMonth = num1.tMonth.value;tDay = num1.tDay.value;tYear = num1.tYear.value;if (!isValidDayOfMonth(tDay,tMonth,tYear)) {var mess, mDays, mMonth, mYear;mDays = getDays(tMonth,tYear);mMonth = longMonths[tMonth-1];mYear = tYearmYear = tYear;mess = "";mess = mess + "There are only ";mess = mess + mDays + " in ";mess = mess + mMonth + " ";mess = mess + mYear;alert(mess);return false;}return true;}