Compilare: user.cpp: In function ‘int Lee()’: user.cpp:34:6: warning: unused variable ‘i’ [-Wunused-variable] int i, j, ans = 1; ^ user.cpp:34:9: warning: unused variable ‘j’ [-Wunused-variable] int i, j, ans = 1; ^ user.cpp: In function ‘int main()’: user.cpp:62:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("castel.in", "r", stdin); ^ user.cpp:63:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("castel.out", "w", stdout); ^ user.cpp:64:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d\n", &M, &N, &K); ^ user.cpp:71:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i][j].x); ^