Compilare: user.cpp: In function ‘int main()’: user.cpp:96:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("desen.in", "r", stdin); ^ user.cpp:97:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("desen.out", "w", stdout); ^ user.cpp:99:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &n); ^ user.cpp:101:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &P [i].x, &P [i].y); ^ user.cpp: In function ‘void query(const int&)’: user.cpp:89:45: warning: ‘s’ may be used uninitialized in this function [-Wmaybe-uninitialized] s = s + sqrt ((double)APM [l1][i].c); ^