Compilare: user.c: In function ‘main’: user.c:39:13: warning: unused variable ‘j’ [-Wunused-variable] int a,i,b,u,j,n,m,x1,y1,x2,y2,r1=0,r2=0; ^ user.c:43:7: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d%d%d",&a,&b,&u); ^ user.c:50:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d%d",&x1,&y1); ^ user.c:54:7: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d",&n); ^ user.c:57:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d%d%d%d",&x1,&y1,&x2,&y2); ^ user.c:62:7: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d",&m); ^ user.c:65:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d%d%d%d",&x1,&y1,&x2,&y2); ^