Compilare: user.c: In function ‘main’: user.c:11:4: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%ld",&n); ^ user.c:12:4: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%ld",&m); ^ user.c:13:25: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] for (j=1; j<=n; j++){fscanf(f,"%ld",&v[i]); //j=0 ^ user.c:34:5: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] { fscanf(f,"%ld %ld",&l,&r); ^ user.c:14:20: warning: ‘i’ may be used uninitialized in this function [-Wmaybe-uninitialized] M[0][j]=v[i]; ^