Problem: A necklace can be described as a string of links ('-') and pearls ('o'), with the last link or pearl connected to the first one.

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You can remove a link or a pearl and insert it between two other existing links or pearls (or between a link and a pearl) on the necklace. This process can be repeated as many times as you like, but you can't throw away any parts.

Can you make the number of links between every two adjacent pearls equal? Two pearls are considered to be adjacent if there is no other pearl between them.

Note that the final necklace should remain as one circular part of the same length as the initial necklace.

Input

The only line of input contains a string s (3 ≤ |s| ≤ 100), representing the necklace, where a dash '-' represents a link and the lowercase English letter 'o' represents a pearl.

Output

Print "YES" if the links and pearls can be rejoined such that the number of links between adjacent pearls is equal. Otherwise print "NO".

You can print each letter in any case (upper or lower).

Examples

Input

<span class="tex-font-style-tt">-o-o--</span>

Output

YES

Input

<span class="tex-font-style-tt">-o---</span>


Output

YES

Input

<span class="tex-font-style-tt">-o---o-</span>


Output

NO

Input

ooo


Output

YES

Solution (in JAVA):

Solution:
import java.util.*; import java.io.*;

public class Exam {


    void solve() throws IOException {
        String s  = readString();
        int businki = 0;
        int niti =  0;
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == '-') niti++;
            if (s.charAt(i) == 'o') businki++;
        }
        if (businki != 0) {
            if (niti % businki == 0) System.out.println("YES");
            else System.out.println("NO");
        }
        else System.out.println("YES");
    }


    public static void main(String[] args) throws IOException {
        new Exam().run();
    }

    BufferedReader in;
    PrintWriter out;
    StringTokenizer tok;

    Exam() {
        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);
        }
        tok = new StringTokenizer("");
    }

    void run() throws IOException {
        solve();
        out.close();
    }


    class Fenwik {
        private long[] t;
        private int length;

        Fenwik(int[] a) {
            this.length = a.length + 100;
            this.t = new long[length];
            for (int i = 0; i < a.length; ++i) this.inc(i, a[i]);
        }

        void inc(int i, int delta) {
            for (; i < this.length; i = i | (i + 1)) t[i] += delta;
        }

        long getSum(int r) {
            long sum = 0;
            for (; r >= 0; r = (r & (r + 1)) - 1) sum += this.t[r];
            return sum;
        }

    }

    String delimiter = " ";

    String readLine() throws IOException {
        return in.readLine();
    }

    String readString() throws IOException {
        while (!tok.hasMoreTokens()) {
            String nextLine = readLine();
            if (null == nextLine) return null;
            tok = new StringTokenizer(nextLine);
        }
        return tok.nextToken(delimiter);
    }

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

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

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

    int[] readIntArray(int b) {
        int a[] = new int[b];
        for (int i = 0; i < b; i++)
            try {
                a[i] = readInt();
            } catch (IOException e) {
                e.printStackTrace();
            }
        return a;
    }

    int[] readSortedIntArray(int size) throws IOException {
        Integer[] array = new Integer[size];
        for (int index = 0; index < size; ++index) array[index] = readInt();
        Arrays.sort(array);
        int[] sortedArray = new int[size];
        for (int index = 0; index < size; ++index) sortedArray[index] = array[index];
        return sortedArray;
    }

    int[] sortedIntArray(int size, int[] array) throws IOException {
        for (int index = 0; index < size; ++index) array[index] = readInt();
        Arrays.sort(array);
        int[] sortedArray = new int[size];
        for (int index = 0; index < size; ++index) sortedArray[index] = array[index];
        return sortedArray;
    }

    int minInt(int... values) {
        int min = Integer.MAX_VALUE;
        for (int value : values) min = Math.min(min, value);
        return min;
    }

    int maxInt(int... values) {
        int max = Integer.MIN_VALUE;
        for (int value : values) max = Math.max(max, value);
        return max;
    }

    long minLong(long... values) {
        long min = Long.MAX_VALUE;
        for (long value : values) min = Math.min(min, value);
        return min;
    }

    long maxLong(long... values) {
        long max = Long.MIN_VALUE;
        for (long value : values) max = Math.max(max, value);
        return max;
    }

    boolean checkIndex(int index, int size) {
        return (0 <= index && index < size);
    }

    int abs(int a) {
        if (a < 0) return -a;
        return a;
    }

}