Compilare: user.cpp: In function ‘void solve()’: user.cpp:113:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i< a[current].size(); ++i) ^ user.cpp:87:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:93:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &x,&y,&cost); ^ user.cpp: In function ‘int main()’: user.cpp:150:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("algoritm.in","r",stdin); ^ user.cpp:151:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("algoritm.out","w",stdout); ^ user.cpp:155:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^