Compilare: In file included from /usr/include/c++/4.8/cassert:43:0, from user.cpp:4: user.cpp: In function ‘void solve()’: user.cpp:97:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert (candidates.size() >= P); ^ user.cpp:98:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t i = 0; i < P; i++) ^ user.cpp: In function ‘void read()’: user.cpp:26:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &N, &M, &D, &P); ^ user.cpp:29:74: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &H[i].from, &H[i].to, &H[i].type, &H[i].danger); ^ user.cpp: In function ‘int main()’: user.cpp:106:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("politie.in", "r", stdin); ^ user.cpp:107:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("politie.out", "w", stdout); ^