#include <bits/stdc++.h>
using namespace std;

// Function
string Minimum_Window(string s, string t)
{

	int m[256] = { 0 };

	// Answer
	int ans = INT_MAX; // length of ans
	int start = 0; // starting index of ans
	int count = 0;

	// creating map
	for (int i = 0; i < t.length(); i++) {
		if (m[t[i]] == 0)
			count++;
		m[t[i]]++;
	}

	// References of Window
	int i = 0;
	int j = 0;

	// Traversing the window
	while (j < s.length()) {
		// Calculations
		m[s[j]]--;
		if (m[s[j]] == 0)
			count--;

		// Condition matching
		if (count == 0) {
			while (count == 0) {
				// Sorting ans
				if (ans > j - i + 1) {
					ans = min(ans, j - i + 1);
					start = i;
				}
				// Sliding I
				// Calculation for removing I

				m[s[i]]++;
				if (m[s[i]] > 0)
					count++;

				i++;
			}
		}
		j++;
	}

	if (ans != INT_MAX)
		return s.substr(start, ans);
	else
		return "-1";
}

int main()
{

	string s = "18881";
	string t = "18";

	cout<<"-->Smallest window that contain all character : "<<endl;
	cout << Minimum_Window(s, t).length();
    return 0;

}