forked from ilikecats/papercats
29 lines
529 B
JavaScript
29 lines
529 B
JavaScript
function Stack(initSize) {
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var len = 0;
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var arr = [];
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this.ensureCapacity = function(size) {
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arr.length = Math.max(arr.length, size || 0);
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};
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this.push = function(ele) {
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this[len] = ele;
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len++;
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};
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this.pop = function() {
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if (len === 0) return;
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len--;
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var tmp = this[len];
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this[len] = undefined;
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return tmp;
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};
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this.isEmpty = function() {
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return len === 0;
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}
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this.ensureCapacity(initSize);
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Object.defineProperty(this, "length", {
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get: function() {
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return len;
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}
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});
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}
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module.exports = Stack;
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