Compilare: user.cpp: In function ‘void Djikstra(int)’: user.cpp:31:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<v[k].size(); ++i) { ^ user.cpp: In function ‘bool BFS()’: user.cpp:51:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<F[k].size(); ++i) { ^ user.cpp: In function ‘int main()’: user.cpp:78:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<v[X].size(); ++i) { ^ user.cpp:66:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("atac2.in", "r", stdin); ^ user.cpp:67:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("atac2.out", "w", stdout); ^ user.cpp:68:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d%d", &n, &m, &U, &X); ^ user.cpp:70:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &oras[i]); ^ user.cpp:73:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &x, &y); ^