Compilare: user.cpp: In function ‘int main()’: user.cpp:76:11: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if( isoperator( s[i] ) ) ^ user.cpp:49:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("evaluare.in", "r", stdin); ^ user.cpp:50:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("evaluare.out", "w", stdout); ^ user.cpp:52:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s + 1); ^ /tmp/cc4t1ACz.o: In function `main': user.cpp:(.text.startup+0x5d): warning: the `gets' function is dangerous and should not be used.