Compilare: user.c: In function ‘main’: user.c:7:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("diagonale.in","r",stdin); ^ user.c:8:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("diagonale.out","w",stdout); ^ user.c:10:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i",&n); ^ user.c:12:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i",&x); ^ user.c:16:8: warning: array subscript is below array bounds [-Warray-bounds] m=a[--i][--j]; ^ user.c:16:6: warning: ‘j’ may be used uninitialized in this function [-Wmaybe-uninitialized] m=a[--i][--j]; ^