Codeforces Round #377 (Div. 2) Exam Solution

/**
 *
 * @author svatantra
 */
import java.io.*;
import java.util.*;

public class Four implements Runnable {

    BufferedReader in;
    PrintWriter out;
    StringTokenizer tok = new StringTokenizer("");

    void init() throws FileNotFoundException {
        try {
            in = new BufferedReader(new FileReader("input.txt"));
            out = new PrintWriter("output.txt");
        } catch (Exception e) {
            in = new BufferedReader(new InputStreamReader(System.in));
            out = new PrintWriter(System.out);
        }
    }

    String readString() throws IOException {
        while (!tok.hasMoreTokens()) {
            try {
                tok = new StringTokenizer(in.readLine(), " :");
            } catch (Exception e) {
                return null;
            }
        }
        return tok.nextToken();
    }

    int readInt() throws IOException {
        return Integer.parseInt(readString());
    }

    int[] readIntArray(int size) throws IOException {
        int[] res = new int[size];
        for (int i = 0; i < size; i++) {
            res[i] = readInt();
        }
        return res;
    }

    long readLong() throws IOException {
        return Long.parseLong(readString());
    }

    double readDouble() throws IOException {
        return Double.parseDouble(readString());
    }

  
    public static void main(String[] args) {
        new Thread(null, new Four(), "", 1l * 200 * 1024 * 1024).start();
    }

    long timeBegin, timeEnd;

    void time() {
        timeEnd = System.currentTimeMillis();
        System.err.println("Time = " + (timeEnd - timeBegin));
    }

    long memoryTotal, memoryFree;

    void memory() {
        memoryFree = Runtime.getRuntime().freeMemory();
        System.err.println("Memory = " + ((memoryTotal - memoryFree) >> 10)
                + " KB");
    }

    public void run() {
        try {
            timeBegin = System.currentTimeMillis();
            memoryTotal = Runtime.getRuntime().freeMemory();
            init();
            solve();
            out.close();
            if (System.getProperty("ONLINE_JUDGE") == null) {
                time();
                memory();
            }
        } catch (Exception e) {
            e.printStackTrace();
            System.exit(-1);
        }
    }

  

   
    int m;
    int num[];
    int st[];
     boolean done[];
     int count[];
    void solve() throws IOException
    {
      
       
       int n=readInt();
        m=readInt();
       
         done=new boolean[m+1];
        count=new int [m+1];
      
      
       num=readIntArray(n);
        st=new int[m+1];
      
       int i;
       for(i=1;i<=m;i++)
       st[i]=readInt();
       int min=0;
       int max=n-1;
        int prev=-1;
        int mid=0;
        boolean midf=false;
        boolean prevf=false;
        while(min<=max)
        {
             mid=(min+max)>>1;
           
            if(can(mid)==true)
            {
               // System.out.print("True for "+mid);
                max=mid-1;
                prev=mid;
                prevf=true;
               
            }
            else
            {
                midf=false;
                min=mid+1;
            }
           
           
        }
        if(can(mid))
         {
             out.println(mid+1);
                   
         }
        else if(prevf)
        {
            out.println(prev+1);
           
        }
        else
        {
            out.print("-1");
        }
           

    }
 
     
     boolean can(int mid)
    {
       // System.out.println("Mid="+mid);
              // System.out.println("m="+m);
                      //System.out.println("Count="+count.length);


        Arrays.fill(done,false);
        Arrays.fill(count,0);
        done[0]=true;
        int i;
        for(i=0;i<=mid;i++){
       
            //System.out.println("Val="+num[i]);
            count[num[i]]++;
        }
       
        int have=count[0];
        int used=0;
        for(i=mid;i>=0;i--)
        {
            if(!done[num[i]])
            {
                have-=st[num[i]];
                count[num[i]]--;
                have+=count[num[i]];
                done[num[i]]=true;
                used+=st[num[i]];
               // System.out.println("used="+used);
               
            }
            else
            {
                if(used>0)
                {
                    used--;
                }
                else
                    have--;
            }
        }
        if(have>=0)
        {
            for(i=1;i<=m;i++)
            {
                if(done[i]==false)
                {
                    return false;
                }
                  
            }
             return true;
        }
        return false;
       
    }


   
}