Compilare: user.cpp: In function ‘int mirror(int)’: user.cpp:6:19: warning: unused variable ‘t’ [-Wunused-variable] int i,image=0,t=1,x,v[4]; ^ user.cpp: In function ‘void backtracking(int, int, int)’: user.cpp:21:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j; ^ user.cpp: In function ‘int main()’: user.cpp:38:9: warning: unused variable ‘i’ [-Wunused-variable] int i,j; ^ user.cpp:38:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j; ^ user.cpp:36:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bilete.in","r",stdin); ^ user.cpp:37:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bilete.out","w",stdout); ^ user.cpp:39:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&k); ^