package main

import (
    "github.com/golang/glog"
    "math"
)

var num=3
func main() {
    ints := []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13}
    for i:=1;i<=int(math.Floor(float64(len(ints)/num)))+1;i++{
        low:=num*(i-1)
        if low>len(ints){
            return
        }
        high:=num*i
        if high>len(ints){
            high=len(ints)
        }
        glog.Info(ints[low:high])
    }
}