a=1+2+3+...+458
a=458*459/2
a=105111
b=168+169+170+...+192 Facem un artificiu
1+2+....167+168+169+...+192 - (1+2+...+167)
192*193/2 - 167*168/2 =
18528 - 14028 =
4500
c=15+16+17+...+52 La fel, adunam 1+2+3 +...+14 si pe urma ii scadem
1+2+3+...+14+15+16+....+52 - (1+2+3+...+14) =
52*53 / 2- 14*15/2 =
1378-105=
1273
iar a-b+c =
105111 - 4500 + 1273 = 101884
