public static int maxRun(String str) {
		int maxRun = 0;
		int at = 0;
		for (;at < str.length(); at++) {
			char ch = str.charAt(at);
			int cur = at + 1;
			while (cur < str.length() && ch == str.charAt(cur)) {
				cur++;
			}
			if (maxRun < (cur - at))
				maxRun = cur - at;
		}
		return maxRun; // YOUR CODE HERE
	}