Compilare: user.cpp: In function ‘void pick_pokemon(int)’: user.cpp:35:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < efficient[pokemon_nr].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:54:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pokemon3.in", "r", stdin); ^ user.cpp:55:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pokemon3.out", "w", stdout); ^ user.cpp:59:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:68:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &eff); ^ user.cpp:80:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &pokemon_nr); ^