fix: update implementation to avoid using an array

Author: steff456

lib/node_modules/@stdlib/string/base/remove-last-grapheme-cluster/lib/main.js

@@ -21,6 +21,7 @@
 // MODULES //
 
 var nextGraphemeClusterBreak = require('@stdlib/string/next-grapheme-cluster-break');
+var numGraphemeClusters = require( '@stdlib/string/num-grapheme-clusters' );
 
 
 // MAIN //
@@ -57,22 +58,29 @@ var nextGraphemeClusterBreak = require('@stdlib/string/next-grapheme-cluster-bre
 * // returns 'fo'
 */
 function removeLast( str, n ) {
-	var idx;
+	var total;
+	var num;
 	var i;
 
-	idx = [];
+	if ( n === 0 ) {
+		return str;
+	}
+
+	total = numGraphemeClusters( str );
+	if ( str === '' || total < n ) {
+		return '';
+	}
+
 	i = 0;
-	while ( i < str.length ) {
+	num = 0;
+	while ( num < total - n ) {
 		i = nextGraphemeClusterBreak( str, i );
+		num += 1;
 		if ( i === -1 ) {
 			break;
 		}
-		idx.push(i);
-	}
-	if ( str === '' || idx.length < n ) {
-		return '';
 	}
-	return str.substring( 0, idx[ idx.length - n ] );
+	return str.substring( 0, i );
 }