import java.math.BigDecimal;
import java.text.DecimalFormat;
import java.util.function.BiFunction;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.stream.LongStream;
import java.util.stream.IntStream;
import java.io.*;
import java.util.*;

public class Main {

    public static void main(String[] args) {
        FastScanner sc = new FastScanner();
        PrintWriter out = new PrintWriter(System.out);

        AtCoder problem = new AtCoder(sc);
        problem.solve(out);

        out.flush();
    }

}

class AtCoder {

    private final int A, B;

    AtCoder(FastScanner sc) {
        A = sc.nextInt();
        B = sc.nextInt();
    }

    void solve(PrintWriter out) {
        if (A == 1 && B == 2 || A == 2 && B == 1) {
            out.println(3);
        } else if (A == 2 && B == 3 || A == 3 && B == 2) {
            out.println(1);
        } else {
            out.println(2);
        }
    }
}

// https://qiita.com/p_shiki37/items/a0f6aac33bf60f5f65e4
    class FastScanner {

        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;

        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            } else {
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }

        private int readByte() {
            if (hasNextByte()) {
                return buffer[ptr++];
            } else {
                return -1;
            }
        }

        private static boolean isPrintableChar(int c) {
            return 33 <= c && c <= 126;
        }

        public boolean hasNext() {
            while (hasNextByte() && !isPrintableChar(buffer[ptr])) {
                ptr++;
            }
            return hasNextByte();
        }

        public String next() {
            if (!hasNext()) {
                throw new NoSuchElementException();
            }
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while (isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }

        public long nextLong() {
            if (!hasNext()) {
                throw new NoSuchElementException();
            }
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while (true) {
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                } else if (b == -1 || !isPrintableChar(b)) {
                    return minus ? -n : n;
                } else {
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }

        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) {
                throw new NumberFormatException();
            }
            return (int) nl;
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }
    }


Measured memory_bytes: 22100