/* マウスhover処理 */

   function getImageIndex (strFldName) {
      nCnt = document.images.length;

       for (nIdx = 0; nIdx < nCnt; nIdx++) {
	      if (document.images[nIdx].id == strFldName)
		     return(nIdx);
       }
       return(0);
   }

   function mouseOverProc (strFldName) {
      nImageIdx = getImageIndex(strFldName);
      document.images[nImageIdx].src = "http://www.tyutyutrain.com/images/" + strFldName + "2.gif";
   }

   function mouseOutProc (strFldName) {
      nImageIdx = getImageIndex(strFldName);
      document.images[nImageIdx].src = "http://www.tyutyutrain.com/images/" + strFldName + ".gif";
   }