Eroare de compilare: user.cpp: In function ‘int cmp(cercuri, cercuri)’: user.cpp:17:13: error: no match for ‘operator[]’ (operand types are ‘cercuri [3011]’ and ‘cercuri’) return (C[a].r<C[b].r); ^ user.cpp:17:20: error: no match for ‘operator[]’ (operand types are ‘cercuri [3011]’ and ‘cercuri’) return (C[a].r<C[b].r); ^ user.cpp:18:1: warning: control reaches end of non-void function [-Wreturn-type] } ^