Problem: Polycarpus just has been out of luck lately! As soon as he found a job in the "Binary Cat" cafe, the club got burgled. All ice-cream was stolen.

On the burglary night Polycarpus kept a careful record of all club visitors. Each time a visitor entered the club, Polycarpus put down character "+" in his notes. Similarly, each time a visitor left the club, Polycarpus put character "-" in his notes. We know that all cases of going in and out happened consecutively, that is, no two events happened at the same time. Polycarpus doesn't remember whether there was somebody in the club at the moment when his shift begun and at the moment when it ended.

Right now the police wonders what minimum number of distinct people Polycarpus could have seen. Assume that he sees anybody coming in or out of the club. Each person could have come in or out an arbitrary number of times.

Input

The only line of the input contains a sequence of characters "+" and "-", the characters are written one after another without any separators. The characters are written in the order, in which the corresponding events occurred. The given sequence has length from 1 to 300 characters, inclusive.

Output

Print the sought minimum number of people

Examples

Input

+-+-+


Output

1


Input

---

Output

3

Solution (in JAVA):

Solution:

import java.io.*;
import java.math.BigInteger;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;

public class Main {

    static final int INF = Integer.MAX_VALUE;

    static void mergeSort(int[] a, int p, int r) {
        if (p < r) {
            int q = (p + r) / 2;
            mergeSort(a, p, q);
            mergeSort(a, q + 1, r);
            merge(a, p, q, r);
        }
    }

    static void merge(int[] a, int p, int q, int r) {
        int n1 = q - p + 1;
        int n2 = r - q;
        int[] L = new int[n1 + 1], R = new int[n2 + 1];
        // int[] L1 = new int[n1 + 1], R1 = new int[n2 + 1];

        for (int i = 0; i < n1; i++) {
            L[i] = a[p + i];
            //  L1[i] = b[p + i];

        }
        for (int i = 0; i < n2; i++) {
            R[i] = a[q + 1 + i];
            // R1[i] = b[q + 1 + i];

        }
        L[n1] = R[n2] = INF;
        // L1[n1] = R1[n2] = INF;

        for (int k = p, i = 0, j = 0; k <= r; k++) {
            if (L[i] <= R[j]) {

                a[k] = L[i++];
                //  b[k] = L1[i++];

            } else {
                a[k] = R[j++];
                // b[k] = R1[j++];

            }
        }
    }

    static void mergeSort(int[] a, int[] b, int[] c, int p, int r) {
        if (p < r) {
            int q = (p + r) / 2;
            mergeSort(a, b, c, p, q);
            mergeSort(a, b, c, q + 1, r);
            merge(a, b, c, p, q, r);
        }
    }

    static void merge(int[] a, int[] b, int[] c, int p, int q, int r) {
        int n1 = q - p + 1;
        int n2 = r - q;
        int[] L = new int[n1 + 1], R = new int[n2 + 1];
        int[] L1 = new int[n1 + 1], R1 = new int[n2 + 1];
        int[] L2 = new int[n1 + 1], R2 = new int[n2 + 1];
        // int[] L2 = new int[n1 + 1], R2 = new int[n2 + 1];

        for (int i = 0; i < n1; i++) {
            L[i] = a[p + i];
            L1[i] = b[p + i];
            L2[i] = c[p + i];
            // L2[i] = a[p + i];
        }
        for (int i = 0; i < n2; i++) {
            R[i] = a[q + 1 + i];
            R1[i] = b[q + 1 + i];
            R2[i] = c[q + 1 + i];
            //  R2[i] = a[q + 1 + i];
        }
        L[n1] = R[n2] = INF;
        L1[n1] = R1[n2] = INF;
        L2[n1] = R2[n2] = INF;
        int j = 0, k = 0;
        for (int i = p; i <= r; i++) {
            if (L[j] < R[k]) {
                a[i] = L[j];
                b[i] = L1[j];
                c[i] = L2[j++];
                //j++;
            } else if ((L[j] > R[k])) {
                a[i] = R[k];
                b[i] = R1[k];
                c[i] = R2[k++];
                //k++;
            } else {
                //des
                if (L1[j] < R1[k]) {
                    a[i] = L[j];
                    b[i] = L1[j];
                    c[i] = L2[j++];
                    //j++;
                } else {
                    a[i] = R[k];
                    b[i] = R1[k];
                    c[i] = R2[k++];
                }
            }

        }
    }

    public static int[] sieve(int n) {
        int a[] = new int[n + 1];
        for (int i = 2; i <= n; i++) {
            a[i] = 1;
        }
        for (int i = 2; i <= Math.sqrt(n); i++) {
            if (a[i] == 1) {
                for (int k = 2; i * k <= n; k++) {
                    a[i * k] = 0;
                }
            }
        }
        return a;
    }

    public static int sum(int a) {
        int su = 0;
        while (a > 0) {
            su += a % 10;
            a /= 10;
        }
        return su;
    }

    public static boolean prime(int n) {
        if (n == 1) {
            return true;
        }

        for (int i = 2; i <= Math.sqrt(n); i++) {
            if (n % i == 0) {
                return false;
            }
        }
        return true;
    }

    public static boolean isvowel(char c) {
        if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' || c == 'y') {
            return true;
        } else {
            return false;
        }
    }

    static long gcd(long a, long b) {
        return b == 0 ? a : gcd(b, a % b);
    }

    static List<Integer> gd(int a, int b) {
        int m = (int) gcd(a, b);
        List<Integer> q = new ArrayList();
        for (int i = 1; i * i <= m; ++i) {
            if (m % i == 0) {
                q.add(i);
                if (i != m / i) {
                    q.add(m / i);
                }
            }
        }
        return q;
    }

    static long sum(long n) {
        return n * (n + 1) / 2;
    }

    static int divisors(int n, int m) {
        if (n - (m + (m * m)) >= 0) {
            return m;
        }
        for (int i = (int) Math.sqrt(m); i >= 1; i--) {
            if (m % i == 0 && n - (m + (m * i)) >= 0) {
                return i;
            }
        }
        return 1;
    }

    static boolean cal(int val, int k, int t) {
        int res = val, p = 1;
        while (val / Math.pow(k, p) > 0) {
            res += val / Math.pow(k, p);
            p++;
        }
        return res >= t;
    }

    static int Last_Ocuu(int[] a, int n, long v) {
        int start = 0, end = n - 1, mid, ans = -1;

        while (start <= end) {
            mid = (start + end) >> 1;
            if (a[mid] < v) {
                ans = mid;
                end = mid - 1;
            } else if (a[mid] >= v) {
                //ans=mid;
                start = mid + 1;
            }

        }
        return ans;
    }

    static int Last_Ocuu(List<Long> a, int n, int i, long v) {
        int sta = 0, end = n - 1, ans = -1;
        while (sta <= end) {
            int mid = (sta + end) >> 1;
            if (a.get(mid) + a.get(i) >= v && mid != i) {
                ans = mid;
                end = mid - 1;
            } else {
                sta = mid + 1;
            }
        }
        return ans;
    }

    static long summtion(int[] a) {
        long s = 0;
        for (int i = 0; i < a.length; i++) {
            s += (long) a[i];
        }
        return s;
    }

    static boolean vv(int i, int j, int n, int m) {
        if (i >= 0 && i < n && j < m && j >= 0) {
            return true;
        }
        return false;
    }

    public static void main(String[] args) throws IOException, ParseException {
        Scannerr in = new Scannerr(System.in);
        PrintWriter or = new PrintWriter(System.out);
        //   BufferedReader b = new BufferedReader(new InputStreamReader(System.in));
             char[] s = in.nextLine().toCharArray();
        int m = 0, p = 0;
        int ans=0;
        for (int i = 0; i < s.length; i++) {
            if (s[i] == '+') {
                if (m == 0) {
                    ans++;
                } else {
                    m--;
                }
                p++;
            } else {
                if (p == 0) {
                    ans++;
                } else {
                    p--;
                }
                m++;
            }
        }
        or.print(ans);
        or.flush();
    }

    static class Scannerr {

        StringTokenizer st;
        BufferedReader br;

        public Scannerr(FileReader fileReader) throws FileNotFoundException {
            br = new BufferedReader(fileReader);
        }

        public Scannerr(InputStream s) throws FileNotFoundException {
            br = new BufferedReader(new InputStreamReader(s));
        }

        public String next() throws IOException {
            while (st == null || !st.hasMoreTokens()) {
                st = new StringTokenizer(br.readLine());
            }
            return st.nextToken();
        }

        public double nextDouble() throws IOException {
            String x = next();
            StringBuilder sb = new StringBuilder("0");
            double res = 0, f = 1;
            boolean dec = false, neg = false;
            int start = 0;
            if (x.charAt(0) == '-') {
                neg = true;
                start++;
            }
            for (int i = start; i < x.length(); i++) {
                if (x.charAt(i) == '.') {
                    res = Long.parseLong(sb.toString());
                    sb = new StringBuilder("0");
                    dec = true;
                } else {
                    sb.append(x.charAt(i));
                    if (dec) {
                        f *= 10;
                    }
                }
            }
            res += Long.parseLong(sb.toString()) / f;
            return res * (neg ? -1 : 1);
        }

        public int nextInt() throws IOException {
            return Integer.parseInt(next());
        }

        public long nextLong() throws IOException {
            return Long.parseLong(next());
        }

        public String nextLine() throws IOException {
            return br.readLine();
        }

        public boolean ready() throws IOException {
            return br.ready();
        }

    }

}

class Pair {

    int ind;
    int val;

    //int min;
    public Pair(int n, int p) {
        ind = n;
        val = p;
        // min = m;
    }

}