Compilare: user.cpp: In function ‘int main()’: user.cpp:12:72: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1, occurences = 1, previous = word[0]; i < word.length(); i++) ^ user.cpp:7:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("compress.in", "r", stdin); ^ user.cpp:8:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("compress.out", "w", stdout); ^