var lastHeight; 

function init() { 

    setHeight(); 

    var tab = document.getElementById("table1");
    lastHeight= tab.clientHeight;

    setInterval(function(){ 

    if(tab.clientHeight!=lastHeight) { 

    setHeight(); 

    lastHeight= tab.clientHeight;

    } 

    },1); 

} 

function setHeight(){ 
    
    var tab = document.getElementById("table1");
    document.getElementsByName("right")[0].height= tab.clientHeight + 20;
}