Compilare: user.cpp: In function ‘int main()’: user.cpp:48:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("fence.in", "r", stdin); ^ user.cpp:49:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("fence.out", "w", stdout); ^ user.cpp:51:78: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d %d %d %d %d %d %d", &var, &n, &m, &val, &no, &su, &ve, &es); ^ user.cpp:56:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &v[i][j]); ^