Compilare: main.cpp: In function 'int main()': main.cpp:86:47: warning: converting to non-pointer type 'char' from NULL [-Wconversion-null] a[ct].v[nrcaract]=NULL; ^~~~ main.cpp:25:32: 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:26:34: 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); ^ main.cpp:28:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s",(s+1)); ^