/in/foo.c: In function 'main':
/in/foo.c:13:5: error: expected ';' before 'while'
     while(n!=0)
     ^~~~~
/in/foo.c:22:2: error: 'else' without a previous 'if'
  else
  ^~~~
/in/foo.c:25:1: error: expected ';' before '}' token
 }
 ^
/in/foo.c:6:6: warning: unused variable 'r' [-Wunused-variable]
  int r=0;
      ^
/in/foo.c:5:8: warning: unused variable 'x' [-Wunused-variable]
  int n,x,y;
        ^