Compilare: user.cpp: In function ‘int main()’: user.cpp:73:9: warning: unused variable ‘o3’ [-Wunused-variable] int o3=0; ^ user.cpp:30:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("insule.in","r",stdin); ^ user.cpp:31:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("insule.out","w",stdout); ^ user.cpp:33:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:36:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%1d",&v[i][j]); ^