Compilare: user.cpp: In function ‘void addapm(int)’: user.cpp:41:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < No[x].size(); ++i){ ^ user.cpp: In function ‘int main()’: user.cpp:80:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < No[x].size();++j) ^ user.cpp:61:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in", "r", stdin); ^ user.cpp:62:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out", "w", stdout); ^ user.cpp:63:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &N, &M); ^ user.cpp:70:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &a, &b, &d); ^