Compilare: user.cpp: In function ‘void read()’: user.cpp:19:14: warning: unused variable ‘p’ [-Wunused-variable] int i, k, p; ^ user.cpp:20:15: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s + 1); ^ user.cpp: In function ‘void rsw()’: user.cpp:69:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("doi.in", "r", stdin); ^ user.cpp:70:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("doi.out", "w", stdout); ^ user.cpp:71:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &t); ^ /tmp/ccW7lLIU.o: In function `read()': user.cpp:(.text+0x105): warning: the `gets' function is dangerous and should not be used.