#include <bits/stdc++.h>

using i64 = long long;

void solve() {
    std::string s;
    std::cin >> s;
    int n = s.size();
    int l = n / 2, r = n - l;
    std::vector < std::vector < int > > val(n, std::vector < int > (n));
    for(int i = 0; i < n; ++i) {
        for(int j = i; j < n; ++j) {
            std::cin >> val[i][j];
            val[j][i] = val[i][j];
        }
    }
    auto lowbit = [&](int x) -> int {
        return x & -x;
    } ;
    int ans = 0, Tans = 0;
    std::vector < int > f(1 << l), g(1 << r);
    std::vector < std::vector < int > > p(l, std::vector < int > (1 << r));
    for(int i = 1; i < (1 << l); ++i) {
        f[i] = f[i ^ lowbit(i)];
        for(int j = 0; j < l; ++j) {
            if(i >> j & 1) {
                f[i] += val[__builtin_ctz(i)][j];
            }
        }
        if(f[i] > ans) {
            ans = f[i];
            Tans = i;
        }
    }
    for(int i = 1; i < (1 << r); ++i) {
        g[i] = g[i ^ lowbit(i)];
        for(int j = 0; j < r; ++j) {
            if(i >> j & 1) {
                g[i] += val[__builtin_ctz(i) + l][j + l];
            }
        }
        for(int j = 0; j < l; ++j) {
            p[j][i] = p[j][i ^ lowbit(i)] + val[j][__builtin_ctz(i) + l];
        }
    }
    std::vector < int > dp(1 << l);
    for(int i = 1; i < (1 << r); ++i) {
        if(g[i] > ans) {
            ans = g[i];
            Tans = i << l;
        }
        for(int j = 1; j < (1 << l); ++j) {
            dp[j] = dp[j ^ lowbit(j)] + p[__builtin_ctz(j)][i];
            if(ans < dp[j] + g[i] + f[j]) {
                ans = dp[j] + g[i] + f[j];
                Tans = j | (i << l);
            }
        }
    }
    std::cout << __builtin_popcount(Tans) << '\n';
    for(int i = 0; i < n; ++i) {
        if(Tans >> i & 1) {
            std::cout << s[i];
        }
    }
    std::cout << '\n';
}

int main() {
    std::cin.tie(nullptr) -> sync_with_stdio(false);
    int T = 1;
    while(T--) solve();
    return 0;
}