C=(1-5-9+13)+(17-21-25+29)+...+(2013-2017-2021+2025)-2029
C=0+0+0+...+0-2029
C=-2029
C = 1 - 5 - 9 + 13 + 17 - 21 - 25 + 29 + ... + 2013 - 2017 - 2021 + 2025 - 2029
= (1 - 5 - 9 + 13) + (17 - 21 - 25 + 29) + ... + (2001 - 2005 - 2009 + 2013) - 2017 - 2021 + 2025 - 2029
= 0 + 0 + ... + 0 - 4042
= -4042