#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<cmath>
#include<climits>
#include<deque> 
#define int long long
#define pii pair<int,int>
#define getchar_unlocked() getchar()
using namespace std;
const int N=5e6+5;
int d,n,x,a[N],idx,tot,ans[N];
deque<pii> q;
inline int read(){
    int s=0,f=1;
    char ch=getchar();
    while(!isdigit(ch)){
        if(ch=='-') f=-1;
        ch=getchar_unlocked();
    }
    while(isdigit(ch)){
        s=(s<<3)+(s<<1)+(ch&15);
        ch=getchar_unlocked();
    }
    return s*f;
}
signed main(){
	//freopen("","r",stdin);
	//freopen("","w",stdout);
	d=read(),n=read();
	for(int i=1;i<=n;i++) a[i]=read(),q.push_back({i,a[i]});
	while(!q.empty()){
		++tot;
//		cout<<tot<<" ";
		pii l=q.front(),r=q.back();
		if(l.second<=r.second) ans[++idx]=l.first,q.pop_front(),x=max(x,l.second+n-tot);
		else ans[++idx]=r.first,q.pop_back(),x=max(x,r.second+n-tot);
//		cout<<l.second+n-tot<<" "<<x<<"\n";
//		cout<<r.second+n-tot<<" "<<x<<"\n";
	}
	printf("%lld\n",x);
	for(int i=idx;i>=1;i--) printf("%lld ",ans[i]);
	return 0;
}
/*
1 10
19 9 12 5 10 7 16 15 17 12
*/