Compilare: main.cpp: In function 'int main()': main.cpp:99:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < apm[nod].size() ; i++){ ~~^~~~~~~~~~~~~~~~~ main.cpp:49:32: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread (buff , 1 , SZ , fin); ^