Compilare: user.cpp: In function ‘void quick(int, int)’: user.cpp:30:9: warning: unused variable ‘m’ [-Wunused-variable] int m, sp; ^ user.cpp: In function ‘int main()’: user.cpp:40:15: warning: unused variable ‘k’ [-Wunused-variable] int n, i, k; ^ user.cpp:42:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("algsort.in", "r", stdin); ^ user.cpp:43:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("algsort.out", "w", stdout); ^ user.cpp:45:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:47:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a [i]); ^