Compilare: user.cpp: In function ‘bool ok(int)’: user.cpp:121:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < op[i].size(); j ++) { ~~^~~~~~~~~~~~~~ user.cpp:56:15: warning: unused variable ‘di1’ [-Wunused-variable] int x,y,z,di1,di2,cnt,s1=0,s2=0,maxim = 0; ^~~ user.cpp:56:19: warning: unused variable ‘di2’ [-Wunused-variable] int x,y,z,di1,di2,cnt,s1=0,s2=0,maxim = 0; ^~~