版本号比较和排序算法的三种实现

// 方法一 前位补0排序
var sort1 = function(){
	var vs = ['1.2.0','1.12.1','0.1','2.2','2.3.4','3.1.1.1.1.1','2','11.2.1','0','100'];
	var zeroLen = 10;
	var vsSplit = vs.map(function(one){
		var sp = one.split('.');
		return sp.map(function(t){
			var s = '';
			for(var i=0;i<zeroLen - t.length;i++){
				s =''+ s;
			}
			return s + t;
		}).join('.');
	});
	return vsSplit.sort(function(a,b){
		return (a>b?1:-1);
	}).map(function(one){
		return one.replace(//g,'');
	});
}
console.log(JSON.stringify(sort1()));

//树+DFS
var sort2 = function(){
	var vs = ['1.2.0','1.12.1','0.1','2.2','2.3.4','3.1.1.1.1.1','2','11.2.1','0','100'];
	var m = {};
	vs.map(function(one){
		var p = m;
		one.split('.').map(function(a){
			p[a] = p[a] || {};
			p = p[a];
		});
		p.last = true;
	})
	// console.log(JSON.stringify(m));
	var l = [];
	var dfs = function(p,t,d){
		if(p.last){
			l.push(t.join('.'));
		}
		for(var k in p){
			if(k!='last'){
				t[d]=k;
				var _t = t.slice(0,d+1);
			//	console.log(_t);
				dfs(p[k],_t,d+1);
			}
		}
	}
	dfs(m,[],0);
	return l;
}
console.log(JSON.stringify(sort2()));

// 方法三 按列比较
var sort3 = function(){
	var vs = ['1.2.0','1.12.1','0.1','2.2','2.3.4','3.1.1.1.1.1','2','11.2.1','0','100'];
	var vsq = vs.map(function(one){
		return one.split('.');
	});
	return vsq.sort(function(a,b){
		var l = a.length < b.length ? a.length : b.length;
		for(var i = 0;i<l;i++){
			if(a[i]*1 != b[i] * 1){
				return a[i]*1 > b[i]*1 ? 1: -1;
			}
		}
		return a.length > b.length ? 1 : -1;
	}).map(function(t){
		return t.join('.');
	});
}

console.log(JSON.stringify(sort3()));