万全之计

Explanation: Very good trick, approach. With the "prudential." 　　Source: "Three Kingdoms Shu Chi Chuan Pang Tong," "pro-wise to be inferior to" Pei Song of the note cited "Jiang Table Biography": "The Prudential Insurance painted out, the meter is also not foolproof." 　　Examples: The above activities are, because the weak into a strong and ~ also. ★ Song Chenliang "on the discretion of the ancient evergreen closed" Thesaurus:  bag of tricks, Be calculated foolproof