Compilare: user.cpp: In function ‘void bfs()’: user.cpp:38:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[nod].size (); ++i) ^ user.cpp: In function ‘bool dijkstra()’: user.cpp:66:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[nod.x].size (); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:143:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < v[i].size (); ++j) ^ user.cpp:89:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("cmcm.in", "r", stdin); ^ user.cpp:90:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("cmcm.out", "w", stdout); ^ user.cpp:94:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d", &n, &m, &e); ^ user.cpp:97:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &x, &y); ^ user.cpp:99:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &cost[x][y]); ^