C++ :

#include <bits/stdc++.h>
using namespace std;
int main()
{
	int a[20],b[20],c[20]={7,9,10,5,8,4,2,1,6,3,7,9,10,5,8,4,2},i,sum=0;
	char d[20]={'1','0','X','9','8','7','6','5','4','3','2'};
	for(i=0;i<17;i++)
	{
		cin>>a[i];
		sum+=a[i]*c[i];
	}
	sum%=11;
	cout<<d[sum]<<endl;
	return 0;
}

Pascal :

var i,zf,m:longint;
    a,b:array[1..17] of longint;
begin
  zf:=0;
  for i:=1 to 17 do read(a[i]);
  b[1]:=a[1]*7;
  b[2]:=a[2]*9;
  b[3]:=a[3]*10;
  b[4]:=a[4]*5;
  b[5]:=a[5]*8;
  b[6]:=a[6]*4;
  b[7]:=a[7]*2;
  b[8]:=a[8]*1;
  b[9]:=a[9]*6;
  b[10]:=a[10]*3;
  b[11]:=a[11]*7;
  b[12]:=a[12]*9;
  b[13]:=a[13]*10;
  b[14]:=a[14]*5;
  b[15]:=a[15]*8;
  b[16]:=a[16]*4;
  b[17]:=a[17]*2;
  for i:=1 to 17 do zf:=zf+b[i];
  m:=zf mod 11;
  case m of
  0:writeln(1);
  1:writeln(0);
  2:writeln('X');
  3:writeln(9);
  4:writeln(8);
  5:writeln(7);
  6:writeln(6);
  7:writeln(5);
  8:writeln(4);
  9:writeln(3);
  10:writeln(2);
end;
end.