Compilare: user.cpp: In function ‘int main()’: user.cpp:54:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pic.in", "r", stdin); ^ user.cpp:55:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pic.out", "w", stdout); ^ user.cpp:58:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &p, &n); ^ user.cpp:59:55: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1; i<=n*(n+1)/2; i++) scanf("%d", &v[i]); ^