Compilare: main.cpp: In function 'int main()': main.cpp:72:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < edge[x].size(); i++){ ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'void Read(int&)': main.cpp:30:42: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(f, MAX, 1, IN), pos = 0; ^ main.cpp:35:42: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(f, MAX, 1, IN), pos = 0; ^ main.cpp: In function 'int main()': main.cpp:61:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("catun.out", "w", stdout); ^