var Stack = function() {
this.data = [];
};
Stack.prototype.print = function() {
return this.data.join(',');
};
Stack.prototype.push = function(element) {
this.data.push(element);
};
Stack.prototype.pop = function() {
return this.data.pop();
};
Stack.prototype.peek = function() {
return this.data[this.data.length - 1];
};
Stack.prototype.isEmpty = function() {
return this.data.length == 0;
};
module.exports = Stack;
// 调用
var Stack = new Stack();
