package chelper;

import io.InputReader;
import io.OutputWriter;
import misc.GCJSolution;

public class TaskA extends GCJSolution {

  public void solve(int testNumber, InputReader in, OutputWriter out) {
    wrapSolve(testNumber, in, out);
  }

  @Override
  public void solve(int testNumber) {
    char[] s = in.nextString().toCharArray();
    int k = in.nextInt();

    int n = s.length;

    boolean[] a = new boolean[n];
    for (int i = 0; i < n; i++) {
      a[i] = s[i] == '+';
    }

    int ans = 0;

    for (int i = 0; i + k - 1 < n; i++) {
      if (!a[i]) {
        for (int j = 0; j < k; j++) {
          a[i + j] ^= true;
        }
        ans++;
      }
    }

    boolean ok = true;

    for (int i = 0; i < n; i++) {
      ok &= a[i];
    }

    if (ok) {
      out.println(ans);
    } else {
      out.println("IMPOSSIBLE");
    }

  }
}