Compilare: user.cpp: In function ‘void bellman()’: user.cpp:27:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < g[x].size(); ++j) { ^ user.cpp:19:9: warning: unused variable ‘x’ [-Wunused-variable] int x, y, z; ^ user.cpp: In function ‘int main()’: user.cpp:49:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.in","r",stdin); ^ user.cpp:50:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bellmanford.out","w",stdout); ^ user.cpp:52:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:55:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &a, &b, &c); ^