Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:80:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < list[node].size(); i++) { ^ user.cpp: In function ‘void solve_color(int)’: user.cpp:129:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 1; i < wh[cc].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:145:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("kdist.in","r",stdin); ^ user.cpp:146:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("kdist.out","w",stdout); ^ user.cpp:148:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ user.cpp:150:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ user.cpp:156:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &col[i]); ^