old = new Array();
function init(){
document.f.t.value = "";
isOp=false;
str=0;
operator="";
}
function puts(value) {
if(!isOp){
document.f.t.value += value;
} else if(isOp){
document.f.t.value = value;
} else{
document.f.t.value = value;
}
isOp = 1;
}
function operator(value) {
value = document.f.t;
isOp = true;
operator = value;
}
function calc() {
str = eval(str + operator + document.f.t.str);
document.f.t.value = str;
}