Compilare: user.cpp: In function ‘int main()’: user.cpp:65:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (j == strlen(A)) { ^ user.cpp:78:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < matches.size(); ++ i) { ^ user.cpp:35:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.in", "r", stdin); ^ user.cpp:36:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.out", "w", stdout); ^ user.cpp:40:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", A); ^ user.cpp:41:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", B); ^