#!/usr/bin/awk -f

BEGIN {
    RS=","
}

{
    spoke[$1]=NR
}

END {
    nxt = 0
    i=NR
    while(++i <= 30000000) {
        if(!(i%1000000))
            printf "."
        if(i == 30000000)
            print "\n"nxt
        else if(i == 2020)
            print nxt
        prev = nxt
        nxt = spoke[prev] ? i - spoke[prev] : 0
        spoke[prev] = i
    }
}