daca in prima zi a rezolvat 1 singura problema
1 + (1 + 5) + (6 + 5) + (11 + 5) = 1 + 6 + 11 + 16 = 34; 34 > 30 (Fals)
daca in prima zi a rezolvat 0 probleme
0 + (0 + 5) + (5 + 5) + (10 + 5) = 0 + 5 + 10 + 15 = 30; 30 = 30 (Adevarat)
deci in prima zi a rezolvat 0 probleme, in a doua 5, in a treia 10, iar in a patra 15.
