Program run time under Linux

How to calculate the program run time, hehe, a lot of complicated procedures,

First, a simple, qsort algorithm, data? Randomly generated:

See, (Of course, in the case of small amounts of data, not feel the difference, but in the case of large amounts of data, there will be a noticeable feeling.) ）

60000000 vs 10000000

There is a difference in time consumption.

 [[email protected "ctest]# time.  33hehe:60000000----------------------------------------before quick Sort------------------------------------------------------after quick sort----------------- okreal 0m17.976s  user 0m17.246ssys 0m0.150s[[em Ail protected] ctest]# time.  / 33hehe:10000000----------------------------------------before quick Sort------------------------------------------------------after quick sort----------------- okreal 0m2.871s  user 0m2.627ssys 0m0.030s 
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