function Pair( i, s )
{
	this.index = i;
	this.str = s;
}

nLines = document.GetLines();

// Create an array
a = new Array( nLines );

status = "Reading lines..."

// Fill the array a with all lines (with returns) in the document.
for( i = 1; i <= nLines; i++ ) {
	if( (i % 1000) == 0 ){
		status = "Reading lines: " + String(i + 1) + "/" + String(nLines);
	}
	var pair = new Pair( i, document.GetLine( i, eeGetLineWithNewLines ) );
	a.push( pair );
}

status = "Sorting lines..."

a.sort( function(a,b){
	if( a.str > b.str ){
		return 1;
	}
	if( a.str < b.str ){
		return -1;
	}
	return a.index - b.index;
});

// Delete duplicate elements.
for( i = 1; i < nLines; i++ ){
	if( (i % 10) == 0 ){
		status = "Deleting duplicate lines: " + String(i + 1) + "/" + String(nLines);
	}
	if( a[i].str == a[i-1].str ){
		a[i].index = 0;  // disable
	}
}

status = "Sorting lines again..."

a.sort( function(a,b){
	return a.index - b.index;
});

var str = "";
for( i = 0; i < nLines; i++ ){
	if( a[i].index != 0 ){
		if( (i % 1000) == 0 ){
			status = "Joining lines: " + String(i + 1) + "/" + String(nLines);
		}
		str += a[i].str;
	}
}

// Replace the entire document with new elements
document.selection.SelectAll();
document.selection.Text = str;
status = "Duplicate lines deleteded."