鷸蚌相爭，漁翁得利 [鹬－－争－渔－－－]

Jyutping wat6 pong5 soeng1 zang1 , jyu4 jung1 dak1 lei6
Pinyin yù bàng xiāng zhēng , yú wēng dé lì

Definitions (CC-CEDICT)
  1. lit. when the snipe and the clam grapple with each other, the fisherman catches them both (idiom)
  2. fig. when two sides are locked in dispute, it's often a third party that benefits