Compilare: user.cpp: In function ‘int main()’: user.cpp:18:15: warning: unused variable ‘x’ [-Wunused-variable] int i, j, x, k, lista; ^ user.cpp:18:18: warning: unused variable ‘k’ [-Wunused-variable] int i, j, x, k, lista; ^ user.cpp:18:21: warning: unused variable ‘lista’ [-Wunused-variable] int i, j, x, k, lista; ^ user.cpp:19:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("take5.in", "r", stdin); ^ user.cpp:20:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("take5.out", "w", stdout); ^ user.cpp:21:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &s); ^ user.cpp:23:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", v+i); ^