Compilare: user.cpp: In function ‘int solve2(long long int, long long int, long long int, long long int)’: user.cpp:36:9: warning: unused variable ‘insol’ [-Wunused-variable] int insol = 0; ^~~~~ user.cpp:37:19: warning: unused variable ‘s1’ [-Wunused-variable] long double s,s1,s2; ^~ user.cpp:37:22: warning: unused variable ‘s2’ [-Wunused-variable] long double s,s1,s2; ^~ user.cpp:39:9: warning: unused variable ‘delta’ [-Wunused-variable] int delta = b * b - 4 * a * (c - d); ^~~~~