function _link00() { location.href = "index.php"; } 

function _link01() { location.href = "sub1_1.php"; } 
function _link0101() { location.href = "sub1_1.php"; } 
function _link0102() { location.href = "sub1_2.php"; } 
function _link0103() { location.href = "sub1_3.php"; } 

function _link02() { location.href = "sub2_1.php"; } 
function _link0201() { location.href = "sub2_1.php"; } 
function _link0202() { location.href = "sub2_2.php"; } 

function _link03() { location.href = "sub3_1.php"; } 
function _link0301() { location.href = "sub3_1.php"; } 
function _link0302() { location.href = "sub3_2.php"; } 
function _link0303() { location.href = "sub3_3.php"; } 
function _link0304() { location.href = "sub3_4.php"; } 
function _link0305() { location.href = "sub3_5.php"; } 
function _link0306() { location.href = "sub3_6.php"; }
function _link0307() { location.href = "sub3_7.php"; }
function _link0308() { location.href = "sub3_8.php"; }
function _link0309() { location.href = "sub3_9.php"; }

function _link04() { location.href = "sub4_1.php"; } 
function _link0401() { location.href = "sub4_1.php"; } 
function _link0402() { location.href = "sub4_2.php"; } 
function _link0403() { location.href = "sub4_3.php"; } 
function _link0404() { location.href = "sub4_4.php"; } 
function _link0405() { location.href = "sub4_5.php"; } 
function _link0406() { location.href = "sub4_6.php"; } 

function _link05() { location.href = "sub5_1.php"; } 
function _link0501() { location.href = "sub5_1.php"; } 

function _link06() { location.href = "sub6_1.php"; } 
function _link0601() { location.href = "sub6_1.php"; } 
function _link0602() { location.href = "sub6_2.php"; } 
function _link0603() { location.href = "sub6_3.php"; }