BEGIN {
    start_time = mktime("2001 01 01 0 0 0")
    end_time = mktime("2001 01 01 3 0 0")
    interval = 10 * 60
    FS = OFS = " "
}
{
    current_time = $1 " " $2
    current_timestamp = mktime(gensub("/", " ", "g", $1) " " gensub(":", " ", "g", $2) " 0")
    while (start_time < current_timestamp) {
        print strftime("%Y", start_time) "/" strftime("%m", start_time) + 0 "/" strftime("%d", start_time) + 0, strftime("%H", start_time) + 0 ":" strftime("%M", start_time), "nan"
        start_time += interval
    }
    print $0
    start_time += interval
}
END {
    while (start_time <= end_time) {
        print strftime("%Y", start_time) "/" strftime("%m", start_time) + 0 "/" strftime("%d", start_time) + 0, strftime("%H", start_time) + 0 ":" strftime("%M", start_time), "nan"
        start_time += interval
    }
}