touch-pad samsung

// IMPORTANT
// DON'T DO IT THIS SOLUTION IS HALF COMPLETE


#include<bits/stdc++.h>
using namespace std;
int n,m,o,num;

int solve(int digits[], int sign[], int op, int val, int num){
  // base case
  if(op>o)return INT_MAX;
  if(val == num)return op;

  // recursive case
  int ans1 = INT_MAX;
  for(int i =0;i<n; i++){
     int x = val*10 + digits[i];
     ans1 = min(ans1,solve(digits,sign,op+1,x,num));
  }

  int ans2 = INT_MAX;
  int x;
  for(int i =0;i<n;i++){
      if(sign[1]==1)x = val + digits[i];
         ans2 = min(ans2, solve(digits,sign,op+2,x,num));
      if(sign[2]==1)x = val - digits[i];
         ans2 = min(ans2, solve(digits,sign,op+2,x,num));
      if(sign[3]==1)x = val *digits[i];
         ans2 = min(ans2, solve(digits,sign,op+2,x,num));
      if(sign[4]==1)x = val/digits[i];
         ans2 = min(ans2, solve(digits,sign,op+2,x,num));
  }
 if(ans2!=INT_MAX)ans2++;
 return min(ans1,ans2);

}

int main(){

   cin>>n>>m>>o;
   int digits[n],sign[5]={0};
   for(int i=0; i<n;i++)cin>>digits[i];
   for(int i =0; i<m;i++){
      int x; cin>>x; sign[x]++;
   }
   cin>>num;
   int ans = INT_MAX;
   for(int i =0;i<n;i++){
      ans = min(ans, solve(digits,sign,1,digits[i],num));
   }
  if(ans!=INT_MAX)cout<<ans<<endl;
  else cout<<-1<<endl;
   return 0;
}