Compilare: user.cpp: In function ‘int main()’: user.cpp:129:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int it=0;it<vec.size();it++,itt++) ^ user.cpp:33:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld2d.in","r",stdin); ^ user.cpp:34:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld2d.out","w",stdout); ^ user.cpp:36:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:38:40: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(car,1,lmax*lmax+2*lmax,stdin); ^