Compilare: user.cpp: In function ‘int main()’: user.cpp:51:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<v.size(); j++) ^ user.cpp:24:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("drum6.in", "r", stdin); ^ user.cpp:25:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("drum6.out", "w", stdout); ^ user.cpp:27:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:29:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", a[i]); ^