/in/foo.c: In function 'main':
/in/foo.c:8:11: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
   scanf("%d",a[i]);
           ^
/in/foo.c:13:16: error: 'i' undeclared (first use in this function)
  for(int j=0;j<i-1;j++)
                ^
/in/foo.c:13:16: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:15:4: error: 'j' undeclared (first use in this function)
  a[j]=x;
    ^