Walgreen Profit Rises 30.5 Pct, Shares Up  CHICAGO (Reuters) - Walgreen Co. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=WAG.N target=/stocks/quickinfo/fullquote"&gt;WAG.N&lt;/A&gt; on Monday posted a  30.5 percent jump in quarterly profit, its largest increase in  four years, boosted by sales of generic drugs and digital photo  processing.