function cislo() {
         var text = document.getElementById("text").value;
         var isNum = true;
         var numbers = "0123456789";
         var index = 0;
         var dec = 0;
         while ((index < text.length) && (isNum)) {
                 isNum = (numbers.indexOf(text.charAt(index)) != -1);
                 if (!isNum) {
                     text = text.substring(0,index) + text.substring(index+1, text.length);
                     document.getElementById("text").value = text;
                 }
                 index++;
         }
}

function cislo2() {
         var text = document.getElementById("text2").value;
         var isNum = true;
         var numbers = "0123456789";
         var index = 0;
         var dec = 0;
         while ((index < text.length) && (isNum)) {
                 isNum = (numbers.indexOf(text.charAt(index)) != -1);
                 if (!isNum) {
                     text = text.substring(0,index) + text.substring(index+1, text.length);
                     document.getElementById("text2").value = text;
                 }
                 index++;
         }
}