Compilare: user.cpp: In function ‘void Read()’: user.cpp:66:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 1; k < I[j].size(); ++k) ^ user.cpp:25:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%lld%d",&N,&M,&K,&D); ^ user.cpp:38:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&cod[i][j]); ^ user.cpp: In function ‘int main()’: user.cpp:91:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cifrul.in","r",stdin); ^ user.cpp:92:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cifrul.out","w",stdout); ^ user.cpp:95:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&tst); ^