Merge($S_{1} , \,  S_{2} ,\, ..., \,  S_{k}$):
		while at least one $S_{i}$ is not empty do
			kmin := minimum value of keys in $S_{1} ,\, ..., \,  S_{k}$;
			for i:=1 to k do
				if kmin = head($S_{i}$)
					then t[i] := head($S_{i}$)
					else t[i] := nil;
			processing-rule( t[1], t[2], ..., t[k] );
		End-Action