巧算(1+3+5+7······+995+997+999)-(2+4+6+8+10·····992+994+996+99

问题描述:

巧算(1+3+5+7······+995+997+999)-(2+4+6+8+10·····992+994+996+99
快点,急求!

(1+3+5+7······+995+997+999)-(2+4+6+8+10·····992+994+996+998+1000)
=(-1)*1000/2
=(-1)*500
=-500