#include<iostream>
#include<cstdio>


using namespace std;

int n, a[1000001];
//shifted by one
bool used[1000003];int lr[1000003];
void read()
{
    //cin>>n;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        //cin>>a[i];
        cin>>a[i];
    }
}

void solve()
{
    int pointer=1;
    for(int i=1;i<=n;i++)
    {
        int c=a[i]+1;
        if(!used[c])
        {
            used[c]=1;
            bool cond1=(lr[c-1]==0);
            bool cond2=(lr[c+1]==0);
            int rw=0, left, right;
            //...0000_x_00000...
            if(cond1&&cond2)
            {
                lr[c]=c;
                rw=c+1;
            }
            //...1111_x_00000...
            else if((!cond1)&&cond2)
            {
                if(lr[c-1]<=(c-1))
                {
                    int left=lr[c-1];
                    int right=c;
                    lr[c-1]=0;
                    lr[c+1]=0;

                    lr[left]=right;
                    lr[right]=left;
                    rw=right+1;
                }
            }

            //...0000_x_1111...
            else if((cond1)&&(!cond2))
            {
                if(lr[c+1]>=(c+1))
                {
                    int left=c;
                    int right=lr[c+1];
                    lr[c-1]=0;
                    lr[c+1]=0;

                    lr[left]=right;
                    lr[right]=left;
                    rw=right+1;
                }
            }
            //...1111_x_1111...
            else if((!cond1)&&(!cond2))
            {
                int left=lr[c-1];
                int right=lr[c+1];
                lr[c-1]=0;
                lr[c+1]=0;

                lr[left]=right;
                lr[right]=left;
                rw=right+1;
            }
            if(c==pointer)
            {
                pointer=rw;
            }
        }
        //cout<<pointer-1<<" ";
        cout<<pointer-1<<" ";
    }
    cout<<endl;
}

int main()
{
#ifdef ONLINE_JUDGE
    freopen("prefmex.in", "r", stdin);
    freopen("prefmex.out", "w", stdout);
#endif
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    read();
    solve();
	return 0;
}