import std;

void main () {
    string S = readln.split[0];

    solve(S);
}

void solve (string S) {
    int ans = 0;

    while ("yukicoder".length <= S.length) {
        if (S[0] == 'y') {
            auto tmp = HowMany_included(S, "yukicoder");
            ans = tmp > ans ? tmp : ans;
        } else {
            S = S[1..$];
        }
    }

    writeln(ans);
}

int HowMany_included (ref string base, string key) {
    if (base.length < key.length) {
        return 0;
    }

    int ret = 0;
    while (key.length <= base.length) {
        bool is_included = true;
        int cut = -1;
        foreach (j; 0..key.length) {
            if (base[j] != key[j]) {
                is_included = false;
                cut = cast(int)j;
                break;
            }
        }
        if (cut == -1) {
            base = base[9..$];
        } else {
            base = base[cut + 1..$];
        }
        if (is_included) {
            ret++;
        } else {
            return ret;
        }
    }

    return ret;
}