approximation algo-rithm的用法和樣例：
例句
- An approximation algorithm is presented for minimizing a nondecreasing supermodular set function, and its performance guarantee is probed.
摘要給出了求解一類上模集函數最小值問題的一種近似演算法，並討論了所給演算法的性能保證。 - Then, a linear time approximation algorithm was developed, which also provided a solution with the same worst case approximation bounds as LP-approximation.
然後設計了一個非常簡單有用的可以和廿近似演算法得到一樣好的近似解的線性時間近似演算法。
