#include<bits/stdc++.h>
using namespace std;

const int nmax=1e5+42;

int n,p,inp[nmax];

void no()
{
    printf("-1\n");
    exit(0);
}

int outp[nmax];

int seen[nmax];

int cnt_seen[nmax];

int main()
{
    freopen("notdecreasing.in","r",stdin);
    freopen("notdecreasing.out","w",stdout);

    scanf("%i%i",&n,&p);
    for(int i=1;i<=n;i++)scanf("%i",&inp[i]);

    for(int i=1;i<n;i++)
        if(inp[i]>inp[i+1])no();

    for(int i=1;i<n;i++)
        if(1LL*inp[i]*p>i)no();

    if(n<p)
    {
        for(int i=1;i<=n;i++)printf("%i ",p+1-i);
        printf("\n");

        exit(0);
    }

    if(p==1)
    {
        for(int i=1;i<=n;i++)
            if(inp[i]!=i)no();

        for(int i=1;i<=n;i++)printf("%i ",1);
        printf("\n");

        exit(0);
    }

    for(int i=1;i<=n;i++)
        if(inp[i-1]!=inp[i])outp[i]=1;

    int cur=p;

    for(int i=1;i<=n;i++)
        if(outp[i]==0)
        {
            outp[i]=cur;
            cur--;

            if(cur==1)cur=p;
        }


    for(int i=1;i<=p;i++)cnt_seen[0]++;

    int mini=0;

    for(int i=1;i<=n;i++)
    {
        cnt_seen[seen[outp[i]]]--;

        seen[outp[i]]++;

        cnt_seen[seen[outp[i]]]++;

        while(cnt_seen[mini]==0)mini++;

        if(mini!=inp[i])no();
    }

    /*
    for(int i=1;i<=p;i++)
        if(seen[i]==0)no();
    */

    for(int i=1;i<=n;i++)printf("%i ",outp[i]);printf("\n");

    return 0;
}