expresie2.cpp: In function 'int main()': expresie2.cpp:66: warning: comparison between signed and unsigned integer expressions expresie2.cpp:81: warning: comparison between signed and unsigned integer expressions expresie2.cpp:25: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result expresie2.cpp:26: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result expresie2.cpp:27: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result /tmp/cc7FXjk3.o: In function `main': expresie2.cpp:(.text+0x296): warning: the `gets' function is dangerous and should not be used.