Problem:
Score : 800 points

Problem Statement

You are given an integer sequence x of length N.
Determine if there exists an integer sequence a that satisfies all of the following conditions, and if it exists, construct an instance of a.

a is N^2 in length, containing N copies of each of the integers 1, 2, ..., N.

For each 1 ≤ i ≤ N, the i-th occurrence of the integer i from the left in a is the x_i-th element of a from the left.

Constraints

1 ≤ N ≤ 500

1 ≤ x_i ≤ N^2

All x_i are distinct.

Input

The input is given from Standard Input in the following format:

N
x_1 x_2 ... x_N

Output

If there does not exist an integer sequence a that satisfies all the conditions, print No.
If there does exist such an sequence a, print Yes in the first line, then print an instance of a in the second line, with spaces inbetween.

Sample Input 1

3
1 5 9

Sample Output 1

Yes
1 1 1 2 2 2 3 3 3

For example, the second occurrence of the integer 2 from the left in a in the output is the fifth element of a from the left.
Similarly, the condition is satisfied for the integers 1 and 3.

Sample Input 2

2
4 1

Sample Output 2

No

Solution in Kotlin (1.3.71) (judge verdict: Accepted)

import java.util.*

fun main() {
    val n= readLine()!!.toInt()
    var x=Array(n+1){IntArray(2){0} }
    val inp= readLine()!!.split(" ").map { it.toInt() }
    var a=IntArray(n*n){0}
    for (i in 1..n){
        x[i][0]=i
        x[i][1]=inp[i-1]-1
        if (x[i][1]<n*n){a[x[i][1]]=i}
    }
    x.sortBy { it[1] }
    var que=ArrayDeque<Int>()
    var cnt=IntArray(2){1}
    var f=true
    var tmp=mutableListOf(x[cnt[1]][0], x[cnt[1]][0]-1)
    for (i in 0 until n*n){
        while (tmp[1]==0 && cnt[1]<=n){
            for (j in 0 until n- x[cnt[1]][0]){
                que.addLast(x[cnt[1]][0])
            }
            cnt[1]++
            if (cnt[1]<=n){
                tmp= mutableListOf(x[cnt[1]][0], x[cnt[1]][0]-1)
            }else{
                tmp= mutableListOf(-1,-1)
            }
        }
        if (cnt[0]<=n&&x[cnt[0]][1]==i){
            cnt[0]++
            continue
        }
        if (cnt[1]<=n&&cnt[0]<=n){
            if (x[cnt[0]][1]>i && tmp[1]>0){
                a[i]=tmp[0]
                tmp[1]--
            }
        }
        if (a[i]==0 && que.isNotEmpty()){a[i]=que.removeFirst()}
    }
    var check=IntArray(n+1){0 }
    var ind=1
    for (i in a.indices){
        check[a[i]]++
        if (a[i]==check[a[i]]){
            if (i!=x[ind][1]){
                f=false
            }else{
                ind++
            }
        }
    }
    if (check[0]!=0){f=false}
    if (f){
        println("Yes")
        println(a.joinToString(separator = " "))
    }else{
        println("No")
    }

}