Compilare: user.cpp: In function ‘void prepare()’: user.cpp:16:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (n != strlen(s)) cerr << "ERROR"; ^ user.cpp: In function ‘int main()’: user.cpp:69:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sirag2.in", "r", stdin); ^ user.cpp:70:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sirag2.out", "w", stdout); ^ user.cpp:72:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ user.cpp:74:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n", &n, &p); ^ user.cpp:75:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/ccXw1bzH.o: In function `main': user.cpp:(.text.startup+0x8c): warning: the `gets' function is dangerous and should not be used.