Expressions (phrases, clauses, etc.), I-adjective (keiyoushi)
not straightforward; not dealt with by ordinary means; very hard to manage
see 一筋縄
先の時間に居眠りした分も合わせて、今度の試験はどうも一筋縄ではいかない感じが漂っている。Taking into account the time I'd just spent napping, I'm really picking up the sense that this time's exam really won't be straight forward.
Also written 一筋縄では行かない【ひとすじなわではいかない】