foo.c: In function 'main':
foo.c:14:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d%d%d",&x,&y,&n,&m,&l);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:19:12: warning: 'len1' may be used uninitialized in this function [-Wmaybe-uninitialized]
         l=l/c;
           ~^~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。