Compilare: user.cpp: In function ‘int main()’: user.cpp:29:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < strlen(a); i ++) { ^ user.cpp:39:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = strlen(a); i < strlen(b); i ++) { ^ user.cpp:45:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < strlen(a); j ++) ^ user.cpp:54:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); i ++) ^ user.cpp:13:39: 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:14:41: 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:22:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(a, N_MAX, stdin); ^ user.cpp:24:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(b, N_MAX, stdin); ^