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所以说百工干事,都有法规可以衡量。现在大道治理天下,其次治理大国,却没有法度来衡量,这就是还不如百工聪明了。 
The use of a program to prove the 4-color theorem will not change mathematics - it merely demonstrates that the theorem, a challenge for a century, is a finite problem.
The coal industry has been the backbone of America's energy independence for generations.