Compilare: user.cpp: In function ‘int main()’: user.cpp:141:11: warning: unused variable ‘aux’ [-Wunused-variable] int aux = -(*sz.begin()); ^~~ user.cpp:123:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nespus.in", "r", stdin); ^ user.cpp:124:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nespus.out", "w", stdout); ^ user.cpp:127:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ user.cpp:129:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &a[i], &b[i], &c[i]); ^