diff --git a/w2v-server.pl b/w2v-server.pl
index 0d6bff3..2d1b874 100644
--- a/w2v-server.pl
+++ b/w2v-server.pl
@@ -151,7 +151,7 @@
 	int N = pars->N;
 	unsigned long from = pars -> from;
 	unsigned long upto = pars -> upto;
-	char file_name[max_size], st[100][max_size];
+	char file_name[max_size], st[100][max_size], sep[100];
 	float dist, len, *bestd, vec[max_size];
 	long long a, b, c, d, cn, bi[100], *besti;
 	char ch;
@@ -173,8 +173,8 @@
 		c++;
 		st[cn][b] = 0;
 		if (st1[c] == 0) break;
-		if (st1[c] == ' ') {
-			cn++;
+		if (st1[c] == ' ' || st1[c] == '-') {
+      sep[cn++] = st1[c];
 			b = 0;
 			c++;
 		}
@@ -198,7 +198,10 @@
 	for (a = 0; a < size; a++) vec[a] = 0;
 	for (b = 0; b < cn; b++) {
 		if (bi[b] == -1) continue;
-		for (a = 0; a < size; a++) vec[a] += M[a + bi[b] * size];
+    if(b>0 && sep[b-1] == '-')
+      for (a = 0; a < size; a++) vec[a] -= M[a + bi[b] * size];
+    else
+      for (a = 0; a < size; a++) vec[a] += M[a + bi[b] * size];
 	}
 	len = 0;
 	for (a = 0; a < size; a++) len += vec[a] * vec[a];