Compilare: main.cpp: In function 'int main()': main.cpp:38:40: warning: converting to non-pointer type 'char' from NULL [-Wconversion-null] nume[nrfold][nrcaract]=NULL; ^~~~ main.cpp:58:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=1;j<=strlen(a[i].ss);j++) ~^~~~~~~~~~~~~~~~~ main.cpp:20:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dir.in","r",stdin); ^ main.cpp:21:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dir.out","w",stdout); ^