• $\textbf{for} \ \forall i \in [1, n]$ 枚举每个中心点
• 二分回文半径 $r$，判断 $[i-mid, i-1]$ 和 $[i+1, i+mid]$ 是否满足回文？
• $\textbf{if}$ 满足回文性质，扩大半径
• $\textbf{else}$ 减少半径

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <queue>
#include <vector>
#include <stack>
#include <map>
#include <set>
#include <sstream>
#include <iomanip>
#include <cmath>
#include <bitset>
#include <assert.h>
#include <unordered_map>

using namespace std;
typedef long long ll;

#define Cmp(a, b) memcmp(a, b, sizeof(b))
#define Cpy(a, b) memcpy(a, b, sizeof(b))
#define Set(a, v) memset(a, v, sizeof(a))
#define debug(x) cout << #x << ": " << x << endl
#define _forS(i, l, r) for(set<int>::iterator i = (l); i != (r); i++)
#define _rep(i, l, r) for(int i = (l); i <= (r); i++)
#define _for(i, l, r) for(int i = (l); i < (r); i++)
#define _forDown(i, l, r) for(int i = (l); i >= r; i--)
#define debug_(ch, i) printf(#ch"[%d]: %d\n", i, ch[i])
#define debug_m(mp, p) printf(#mp"[%d]: %d\n", p->first, p->second)
#define debugS(str) cout << "dbg: " << str << endl;
#define debugArr(arr, x, y) _for(i, 0, x) { _for(j, 0, y) printf("%c", arr[i][j]); printf("\n"); }
#define _forPlus(i, l, d, r) for(int i = (l); i + d < (r); i++)
#define lowbit(i) (i & (-i))
#define MPR(a, b) make_pair(a, b)

pair<int, int> crack(int n) {
    int st = sqrt(n);
    int fac = n / st;
    while (n % st) {
        st += 1;
        fac = n / st;
    }

    return make_pair(st, fac);
}

inline ll qpow(ll a, int n) {
    ll ans = 1;
    for(; n; n >>= 1) {
        if(n & 1) ans *= 1ll * a;
        a *= a;
    }
    return ans;
}

template <class T>
inline bool chmax(T& a, T b) {
    if(a < b) {
        a = b;
        return true;
    }
    return false;
}

ll gcd(ll a, ll b) {
    return b == 0 ? a : gcd(b, a % b);
}

ll ksc(ll a, ll b, ll mod) {
    ll ans = 0;
    for(; b; b >>= 1) {
        if (b & 1) ans = (ans + a) % mod;
        a = (a * 2) % mod;
    }
    return ans;
}

ll ksm(ll a, ll b, ll mod) {
    ll ans = 1 % mod;
    a %= mod;

    for(; b; b >>= 1) {
        if (b & 1) ans = ksc(ans, a, mod);
        a = ksc(a, a, mod);
    }

    return ans;
}

template <class T>
inline bool chmin(T& a, T b) {
    if(a > b) {
        a = b;
        return true;
    }
    return false;
}

template<class T>
bool lexSmaller(vector<T> a, vector<T> b) {
    int n = a.size(), m = b.size();
    int i;
    for(i = 0; i < n && i < m; i++) {
        if (a[i] < b[i]) return true;
        else if (b[i] < a[i]) return false;
    }
    return (i == n && i < m);
}

// ============================================================== //

typedef unsigned long long ull;
const int maxn = 2000000 + 10, P = 131;
char str[maxn];
int n;
ull hl[maxn], hr[maxn], p[maxn];

void prework() {
    for (int i = n*2; i >= 1; i -= 2) {
        str[i] = str[i/2];
        str[i-1] = 'z' + 1;
    }
    n *= 2;

    p[0] = 1;
    for (int i = 1, j = n; i <= n; i++, j--) {
        hl[i] = hl[i-1] * P + str[i] - 'a' + 1;
        hr[i] = hr[i-1] * P + str[j] - 'a' + 1;
        p[i] = p[i-1] * P;
    }
}

ull get(const ull h[], int l, int r) {
    return h[r] - h[l-1] * p[r-l+1];
}

void solve() {
    int ans = 0;
    for (int i = 1; i <= n; i++) {
        int l = 0, r = min(i-1, n-i);
        while (l < r) {
            int mid = (l + r + 1) >> 1;
            if (get(hl, i-mid, i-1) != get(hr, n+1-(i+mid), n+1-(i+1))) r = mid - 1;
            else l = mid;
        }
        // ans is l
        if (str[i-l] <= 'z') ans = max(ans, l+1);
        else ans = max(ans, l);
    }
    printf("%d\n", ans);
}

int main() {
    freopen("input.txt", "r", stdin);
    int kase = 0;
    while (scanf("%s", str+1) && str[1] != 'E') {
        n = strlen(str+1);
        printf("Case %d: ", ++kase);

        // prework
        prework();

        // then solve
        solve();
    }
}