#include <bits/stdc++.h>
using namespace std;
int main()
{
int n;
string s;
cin >> n >> s;
int best = 1, cur = 1;
for (int i = 1; i < n; i++)
{
if (s[i] == s[i - 1])
cur++;
else
cur = 1;
best = max(best, cur);
}
cout << best << '\n';
return 0;
}
