Compilare: user.cpp: In function ‘int main()’: user.cpp:62:24: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 2 has type ‘unsigned int’ [-Wformat=] printf("%lld\n",ans); ^ user.cpp:18:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("abc2.in","r",stdin); ^ user.cpp:19:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("abc2.out","w",stdout); ^ user.cpp:20:15: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(st+1); ^ user.cpp:22:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(stt+1); ^ user.cpp:36:20: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(stt+1); ^ /tmp/ccGj3efh.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.