/in/foo.c: In function 'main':
/in/foo.c:17:14: warning: implicit declaration of function 'abs' [-Wimplicit-function-declaration]
    x[j]=x[j]+abs(a[i]-m);
              ^~~
/in/foo.c:9:10: warning: unused variable 'k' [-Wunused-variable]
  int i,j,k,m;
          ^