Another update from ingydotnet^djgoku

Task/Longest-common-subsequence/JavaScript/longest-common-subsequence-4.js

@@ -1,27 +1,15 @@
-function lcs_greedy(x,y){
-	var symbols = {},
-		r=0,p=0,p1,L=0,idx,
-		m=x.length,n=y.length,
-		S = new Buffer(m<n?n:m);
-	p1 = popsym(0);
-	for(i=0;i < m;i++){
-		p = (r===p)?p1:popsym(i);
-		p1 = popsym(i+1);
-		idx=(p > p1)?(i++,p1):p;
-		if(idx===n){p=popsym(i);}
-		else{
-			r=idx;
-			S[L++]=x.charCodeAt(i);
+	var t=i;
+	while(i>-1&&j>-1){
+		switch(c[i][j]){
+			default:i--,j--;
+				continue;
+			case (i&&c[i-1][j]):
+				if(t!==i){lcs.unshift(x.substring(i+1,t+1));}
+				t=--i;
+				continue;
+			case (j&&c[i][j-1]): j--;
+				if(t!==i){lcs.unshift(x.substring(i+1,t+1));}
+				t=i;
 		}
 	}
-	return S.toString('utf8',0,L);
-	
-	function popsym(index){
-		var s = x[index],
-			pos = symbols[s]+1;
-		pos = y.indexOf(s,pos>r?pos:r);
-		if(pos===-1){pos=n;}
-		symbols[s]=pos;
-		return pos;
-	}
-}
+	if(t!==i){lcs.unshift(x.substring(i+1,t+1));}