Compilare: user.cpp: In function ‘bool solve()’: user.cpp:65:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 1; i + 1 < way.size(); i++) ^ user.cpp:72:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < way.size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:100:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fantasy.in","r",stdin); ^ user.cpp:101:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fantasy.out","w",stdout); ^ user.cpp:103:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ user.cpp:105:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &n, &D, &C, &V); ^ user.cpp:107:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^