Compilare: user.c: In function ‘main’: user.c:8:8: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ user.c:9:8: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&m); ^ user.c:12:10: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%ld",&A[i][j]); ^ user.c:76:7: warning: ‘sum’ may be used uninitialized in this function [-Wmaybe-uninitialized] sum+=A[i][j]; ^