Compilare: user.cpp: In function ‘int main()’: user.cpp:23:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("largestroot.in","r",stdin); ^ user.cpp:24:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("largestroot.out","w",stdout); ^ user.cpp:26:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (scanf("%lld\n", &T); T ; --T) ^ user.cpp:28:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld\n", &n); ^ user.cpp:34:38: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] ok = false; gets(sir + 1); m = strlen(sir + 1); if (sir[1] == '-') ok = true; ^ /tmp/cciYqrr7.o: In function `main': user.cpp:(.text.startup+0x261): warning: the `gets' function is dangerous and should not be used.