#include<cstdio>
#include<cstdlib>
#include<iostream>
#include<vector>
#include<queue>
#include<bitset>
#include<string>
#include<stack>
#include<set>
#include<unordered_set>
#include<map>
#include<unordered_map>
#include<cstring>
#include<complex>
#include<cmath>
#include<iomanip>
#include<numeric>
#include<algorithm>
#include<list>
#include<functional>
#include<cassert>
#define mp make_pair
#define pb push_back
#define X first
#define Y second
#define y0 y12
#define y1 y22
#define INF 987654321
#define PI 3.141592653589793238462643383279502884
#define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
#define fdn(i,a,b,c) for(int (i)=(a);(i)>=(b);(i)-=(c))
#define MEM0(a) memset((a),0,sizeof(a));
#define MEM_1(a) memset((a),-1,sizeof(a));
#define ALL(a) a.begin(),a.end()
#define SYNC ios_base::sync_with_stdio(false);cin.tie(0)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> Pi;
typedef pair<ll, ll> Pll;
typedef pair<ld, ld> Pd;
typedef vector<int> Vi;
typedef vector<ll> Vll;
typedef vector<double> Vd;
typedef vector<Pi> VPi;
typedef vector<Pll> VPll;
typedef vector<Pd> VPd;
typedef tuple<int, int, int> iii;
typedef tuple<int,int,int,int> iiii;
typedef tuple<ll, ll, ll> LLL;
typedef vector<iii> Viii;
typedef vector<LLL> VLLL;
typedef complex<double> base;
const int MOD = 998244353;
ll POW(ll a, ll b, ll MMM = MOD) {ll ret=1; for(;b;b>>=1,a=(a*a)%MMM)if(b&1)ret=(ret*a)% MMM; return ret; }
ll gcd(ll a, ll b) { return b ? gcd(b, a%b) : a; }
ll lcm(ll a, ll b) { if (a == 0 || b == 0)return a + b; return a*(b / gcd(a, b)); }
int dx[] = { 0,1,0,-1,1,1,-1,-1 }, dy[] = { 1,0,-1,0,1,-1,1,-1 };
int ddx[]={2,2,-2,-2,1,1,-1,-1},ddy[]={1,-1,1,-1,2,-2,2,-2};

int k,d[305][305][305];
char s[305];
int go(int l,int r,int K)
{
	if(K<0)return -INF;
	if(l==r)return 1;
	if(l>r)return 0;
	int &ret=d[l][r][K];
	if(~ret)return ret;
	ret=max({go(l+1,r-1,K-(s[l]!=s[r]))+2,go(l+1,r,K),go(l,r-1,K)});
	return ret;
}
int main(){
	MEM_1(d);
	scanf("%s%d",s,&k);
	printf("%d",go(0,strlen(s)-1,k));
}
#include <bits/stdc++.h>
#define ll long long
#define maxn 100005 /*rem*/
#define mod 998244353
#define db double
#define vi vector<int>
#define pb push_back
#define mp make_pair
#define pi pair<int, int>
#define fi first
#define se second
using namespace std;
int a[maxn];
int n, m;
int f[maxn], cnt = 0;
bool cmp(int a, int b) {
	return (a % 2) > (b % 2);
}
int pl;
void push(int a) {
	if (pl + a - 1 >= n) a = n + 1 - pl;
	f[cnt++] = a, pl += a;
}
int main() {
	cin >> n >> m;
	for (int i = 0; i < m; i++)
		cin >> a[i];
	sort(a, a + m, cmp);
	int ans = 0;
	for (int i = 0; i < m; i++)
		ans += a[i] % 2;
	if (n % 2 == 0 && ans > 2) cout << "Impossible" << endl;
	else if (n % 2 == 1 && ans > 1) cout << "Impossible" << endl;
	else {
		pl = 1;
		if (a[1] % 2) swap(a[1], a[m - 1]);
		for (int i = 0; i < m; i++) {
			if (a[i] % 2) {
				if (i == 0) 
					for (int j = 0; j < a[i] / 2 + 1; j++)
						push(2);
				else for (int j = 0; j < a[i] / 2; j++)
					push(2);
			}
			else {
				if (i == 0) push(1);
				push(a[i]);
			}
		}
		for (int i = 0; i < m; i++)
			cout << a[i] << ' ';
		cout << endl;
		cout << cnt << endl;
		for (int i = 0; i < cnt; i++)
			printf("%d ", f[i]);
		printf("\n");
	}
	return 0;
}
