Compilare: user.cpp: In function ‘int main()’: user.cpp:23:7: warning: unused variable ‘st’ [-Wunused-variable] int st = 0, last = -1; ^ user.cpp:15:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("parpal.in", "r", stdin); ^ user.cpp:16:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("parpal.out", "w", stdout); ^ user.cpp:17:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ user.cpp:19:10: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/ccivipRB.o: In function `main': user.cpp:(.text.startup+0x86): warning: the `gets' function is dangerous and should not be used.