Compilare: user.cpp: In function ‘void dfs(int, int, char*)’: user.cpp:29:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( i = 0; i < v[ k ].size(); ++i ){ ^ user.cpp:23:12: warning: unused variable ‘ok’ [-Wunused-variable] int i, ok; ^ user.cpp:24:10: warning: unused variable ‘x’ [-Wunused-variable] char x; ^ user.cpp: In function ‘int main()’: user.cpp:44:15: warning: unused variable ‘j’ [-Wunused-variable] int n, i, j, t, d, x, y; ^ user.cpp:44:18: warning: unused variable ‘t’ [-Wunused-variable] int n, i, j, t, d, x, y; ^ user.cpp:44:21: warning: unused variable ‘d’ [-Wunused-variable] int n, i, j, t, d, x, y; ^ user.cpp:41:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arbpal.in","r",stdin); ^ user.cpp:42:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arbpal.out","w",stdout); ^ user.cpp:47:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:49:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^ user.cpp:54:54: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for( i = 1; i <= n; ++i) scanf("%*c%c",&car[ i ]); ^