比较两个字符串相似度 Levenshtein_Distance_Percent

//求两个字符串的相似度,返回差别字符数,Levenshtein Distance算法实现
function Levenshtein_Distance(s,t){
	var n=s.length;// length of s
	var m=t.length;// length of t
	var d=[];// matrix
	var i;// iterates through s
	var j;// iterates through t
	var s_i;// ith character of s
	var t_j;// jth character of t
	var cost;// cost
	// Step 1
	if (n == 0) return m;
	if (m == 0) return n;
	// Step 2
	for (i = 0; i <= n; i++) {
		d[i]=[];
		d[i][0] = i;
	}
	for (j = 0; j <= m; j++) {
		d[0][j] = j;
	}
	// Step 3
	for (i = 1; i <= n; i++) {
		s_i = s.charAt (i - 1);		
		// Step 4		
		for (j = 1; j <= m; j++) {
			t_j = t.charAt (j - 1);
			// Step 5
			if (s_i == t_j) {
				cost = 0;
			}else{
				cost = 1;
			}
			// Step 6			
			d[i][j] = Minimum (d[i-1][j]+1, d[i][j-1]+1, d[i-1][j-1] + cost);
		}
	}
	// Step 7
	return d[n][m];
}

//求两个字符串的相似度,返回相似度百分比
function Levenshtein_Distance_Percent(s,t){
	var l=s.length>t.length?s.length:t.length;
	var d=Levenshtein_Distance(s,t);
	return (1-d/l).toFixed(4);
}

//求三个数字中的最小值
function Minimum(a,b,c){
	return a