#include<bits/stdc++.h>
using namespace std;
//const long long mod=4294967296;
string mod="4294967296";
const int MAXN=1e7+10;
string bi[MAXN];
string ai[MAXN];
void del0(string &a)
{
    int br=0;
    while(a[br]=='0')br++;
    a.erase(0,br);
}
bool srv(string &a, string &b)
{
    del0(a);
    del0(b);
    if(a.size()!=b.size())return a.size() > b.size();
    return a>=b;
}
string sub(string a,string b)
{
    string res="";
    int pre=0;
    while(a.size()<b.size())a="0"+a;
    while(b.size()<a.size())b="0"+b;
    for(int i=a.size()-1;i>=0;i--)
    {
        int tmp=(a[i]-'0')+(b[i]-'0')+pre;
        if(tmp>=10)
        {
            tmp-=10;
            pre=1;
        }
        else pre=0;
        res=char(tmp+'0')+res;
    }
    if(pre)res="1"+res;
    return res;
}
string izv(string a,string b)
{
    int zaem=0;
    string res="";
    while(a.size()<b.size())a="0"+a;
    while(b.size()<a.size())b="0"+b;
    if(a==b)return "0";
    if(a<b)swap(a,b);
    for(int i=a.size()-1;i>=0;i--)
    {
        int tmp=(a[i]-b[i])-zaem;
        if(tmp<0)
        {
            zaem=1;
            tmp+=10;
        }
        else zaem=0;
        res=char(tmp+'0')+res;
    }
    del0(res);
    return res;
}
string umn(string a,string b)
{
      string res;
      int pre=0,i,j;
      res.resize(a.size()+b.size(),'0');
      for(i=a.size()-1;i>=0;i--)
      {
          for(j=b.size()-1;j>=0;j--)
          {
              int tmp=(a[i]-'0')*(b[j]-'0')+(res[i+j+1]-'0')+pre;
              pre=tmp/10;
              tmp%=10;
              res[i+j+1]=tmp+'0';
          }
      res[i+j+1]=pre+'0';
      pre=0;
      }
      res=char(pre+'0')+res;
      del0(res);
      return res;
}
pair<string,string> del(string a,string b)
{
        string res="";
        int L1=a.size();
        int L2=b.size();
        string part=a.substr(0,L2-1);
        for(int i=L2-1;i<L1;i++)
        {
            int br=0;
            part=part+a[i];

            while(srv(part,b))
            {
                part=izv(part,b);
                br++;
            }
            res+=char(br+'0');

        }
        del0(res);
        return {res,part};
}
string power(string x, string y)
{
    string res ="1";
    while (y !="")
    {
        if ((y[y.size()-1]-'0') % 2 == 1)res = del(umn(res , x),mod).second;
        y = del(y,"2").first;
        x = del(umn(x , x),mod).second;
    }
    return del(res , mod).second;
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    freopen("power.in","r",stdin);
    freopen("power.out","w",stdout);
    int a,b,c,d,n;
    cin>>a>>b>>c>>d>>n;
    string sc="";
    string sd="";
    string sa="";
    while(b>0)
    {
        bi[0]+=char(b%10+'0');
        b/=10;
    }
    reverse(bi[0].begin(),bi[0].end());
    while(c>0)
    {
        sc+=char(c%10+'0');
        c/=10;
    }
    reverse(sc.begin(),sc.end());
    while(d>0)
    {
        sd+=char(d%10+'0');
        d/=10;
    }
    reverse(sd.begin(),sd.end());
    while(a>0)
    {
        sa+=char(a%10+'0');
        a/=10;
    }
    reverse(sa.begin(),sa.end());
    for(int i=1; i<=n; i++)
    {
       bi[i]=del((sub(del(umn(bi[i-1],sc),mod).second,sd)),mod).second;
        //bi[i]=umn(bi[i-1],sc);
       //cout<<bi[i]<<endl;
    }
    ai[1]=power(sa,bi[1]);
    //cout<<ai[0]<<endl;
    for(int i=2; i<=n; i++)
    {
        ai[i]=power(sa,bi[i]);
        //cout<<ai[i]<<endl;
    }
    long long otg=0;
    for(int j=0;j<ai[1].size();j++)
        {
            otg=otg*10+ai[1][j]-'0';
        }
       // cout<<otg<<endl;
    for(int i=2;i<=n;i++)
    {
        long long ch=0;
        for(int j=0;j<ai[i].size();j++)
        {
            ch=ch*10+ai[i][j]-'0';
        }
        //cout<<ai[i]<<" "<<ch<<endl;
        otg^=ch;
    }
    cout<<otg<<endl;
    return 0;
}