Compilare: user.cpp: In function ‘std::string getFile()’: user.cpp:19:26: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] while (s[ind] >= 'a' && s[ind] <= 'z' || s[ind] >= 'A' && s[ind] <= 'Z' || ^ user.cpp:20:26: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] s[ind] >= '0' && s[ind] <= '9') ^ user.cpp: In function ‘int fis(std::string)’: user.cpp:27:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < alf.size(); i++) ^ user.cpp:28:29: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (!(alf[i] >= 'a' && alf[i] <= 'z' || s[ind] >= '0' && s[ind] <= '9')) ^ user.cpp: In function ‘void solve()’: user.cpp:41:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (ind < strlen(s)) ^ user.cpp: In function ‘int main()’: user.cpp:75:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); i++) ^ user.cpp:68:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dir.in", "r", stdin); ^ user.cpp:69:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dir.out", "w", stdout); ^ user.cpp:71:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/ccK7nxN5.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.