Compilare: user.cpp: In function ‘int main()’: user.cpp:29:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("senat.in","r",stdin); ^ user.cpp:30:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("senat.out","w",stdout); ^ user.cpp:32:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n",&right,&left); ^ user.cpp:38:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/ccjrSDrG.o: In function `main': user.cpp:(.text.startup+0x9a): warning: the `gets' function is dangerous and should not be used.