Compilare: user.cpp: In function ‘void solve()’: user.cpp:72:24: warning: unused variable ‘a’ [-Wunused-variable] int i, p1, p2, p3, a, b, c; ^ user.cpp:72:27: warning: unused variable ‘b’ [-Wunused-variable] int i, p1, p2, p3, a, b, c; ^ user.cpp:72:30: warning: unused variable ‘c’ [-Wunused-variable] int i, p1, p2, p3, a, b, c; ^ user.cpp: In function ‘void read()’: user.cpp:65:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rubarba.in", "r", stdin); ^ user.cpp:66:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:68:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &v[i].x, &v[i].y); ^ user.cpp: In function ‘void write()’: user.cpp:115:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rubarba.out", "w", stdout); ^ user.cpp: In function ‘void solve()’: user.cpp:72:20: warning: ‘p3’ may be used uninitialized in this function [-Wmaybe-uninitialized] int i, p1, p2, p3, a, b, c; ^