Compilare: user.cpp: In function ‘int main()’: user.cpp:80:12: warning: unused variable ‘u’ [-Wunused-variable] int i, u, j, k, ans = 0; ^ user.cpp:80:18: warning: unused variable ‘k’ [-Wunused-variable] int i, u, j, k, ans = 0; ^ user.cpp:82:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("pscpld2d.in", "r", stdin); ^ user.cpp:83:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("pscpld2d.out", "w", stdout); ^ user.cpp:85:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d\n", &n); ^ user.cpp:87:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%s", s [i] + 1); ^