#include 
    
     #define DBG(x) cerr << #x << " = " << x << endltypedef long long LL;using namespace std;int main(int argc, char **argv) {    string str;    while(cin >> str) {        unordered_map
     
       vis;        int ans = INT_MAX;        int l = 0, r = 0;        ++vis[str[r]];        int num = 1;        while(l <= r && r < str.size()) {            if(num == 26) {                ans = min(ans, r - l + 1);                if(--vis[str[l++]] == 0) --num;            } else {                if(vis[str[++r]]++ == 0) ++num;            }        }        if(ans == INT_MAX) cout << "No Solution" << endl;        else cout << ans << endl;    }    return 0;}/**BVCABCDEFFGHIJKLMMNOPQRSTUVWXZYZZ28*/