Compilare: user.cpp: In function ‘int main()’: user.cpp:10:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bemo.in","r",stdin); ^ user.cpp:11:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bemo.out","w",stdout); ^ user.cpp:12:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d ",&n,&m); ^ user.cpp:15:13: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp:16:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf(" "); ^ /tmp/ccHxggIw.o: In function `main': user.cpp:(.text.startup+0x97): warning: the `gets' function is dangerous and should not be used.