朝秦暮楚 zhāo qín mù chǔ

zhāo qín mù chǔ set phrase serve Qin in the morning and Chu in the evening; to change sides quickly
Domain: Idiom 成语
Notes: (CC-CEDICT '朝秦暮楚'; Guoyu '朝秦暮楚'; Mathews 1931 '朝秦暮楚', p. 26)