D=12.3+13.4+14.5+…+119.20A=11.3+13.5+15.7+…+119.20c=19.10-18.9-17.8-…-12.3-12.1H=13-35+57-79+911-1113+1315+1113-911+79-57+35-13k=17.11+111.15+115.19+…+12011.2015M=12013.2012-12012.2011-12011.2010-...-13.2-12.1
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