Compilare: user.cpp: In function ‘void back(int, int)’: user.cpp:80:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int u=0;u<H[line].size();++u) ^ user.cpp: In function ‘int main()’: user.cpp:139:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<pos.size();++j) ^ user.cpp: In function ‘int readInt()’: user.cpp:43:40: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer,1,BSIZE,stdin); ^ user.cpp:54:40: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer,1,BSIZE,stdin); ^ user.cpp: In function ‘int main()’: user.cpp:97:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("autobuze.in","r",stdin); ^ user.cpp:98:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("autobuze.out","w",stdout); ^ user.cpp:100:28: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer,1,BSIZE,stdin); ^