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package index
import (	"fmt"	"math/big"	"strconv"	"strings")
var factorials = make([]*big.Int, 10001)
func initialization() {	if factorials[0] == nil {		var i int64 = 0		for ; i <= 10000; i++ {			if i == 0 {				factorials[i] = big.NewInt(1)			} else {				factorials[i] = new(big.Int).Mul(factorials[i-1], big.NewInt(i))			}
		}	}}
func abbreviateProduct(left, right int) string {	initialization()	var s string	if left == right {		s = strconv.Itoa(left)	} else {		s = new(big.Int).Div(factorials[right], factorials[left-1]).String()	}	tz := len(s)	s = strings.TrimRight(s, "0")	tz -= len(s)	if len(s) > 10 {		return fmt.Sprintf("%s...%se%d", s[:5], s[len(s)-5:], tz)	}	return fmt.Sprintf("%se%d", s, tz)}