Compilare: main.cpp: In function 'void dfs(long int)': main.cpp:26:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0 ; i < lista[nod].size() ; ++ i) { ~~^~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:61:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (lista[x].size() == v - 1) { ~~~~~~~~~~~~~~~~^~~~~~~~ main.cpp:51:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("divisorgraph.in", "r", stdin) ; ^ main.cpp:52:44: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("divisorgraph.out", "w", stdout) ; ^ main.cpp:54:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%ld", &querys) ; ^ main.cpp:57:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%ld %ld", &v, &e) ; ^ main.cpp:59:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%ld %ld", &x, &y) ; ^