Codechef TSORT (Turbo Sort)

tsort.go

package main

import (
	"os"
)

//google.com/+robertking
//fastest go solutions:
//http://www.codechef.com/status/TSORT?sort_by=Time&sorting_order=asc&language=114&status=15&handle=&Submit=GO
//(It's 3.8x slower than C & C++. Slightly faster than Java.) 

func main() {
	data := make([]byte, 1000001 * 7)
	counts := make([]int, 1000001)
	os.Stdin.Read(data)
	i := 0
	T := 0
	//read number of cases
	for ;;i++ {
		if (data[i] == '\n') {
			i++
			break;
		}
		T *= 10;
		T += int(data[i] - '0')
	}
	x := 0
	//get counts for each number
	for ;;i++ {
		if (data[i] == '\n' || data[i] == 0) {
			counts[x]++
			T--
			if (T == 0) {
				break
			}
			x = 0;
		} else {
			x = (x<<3) + (x<<1) + int(data[i] - '0')
		}
	}
	//write output
	bytes := make([]byte, 1000001 * 7)
	j := 0
	for x := len(counts) - 1; x >= 0; x-- {
		c := counts[x]
		for ; c > 0; c-- {
			x2 := x
			for {
				bit := x2 % 10
				if (x2 < 1029) {
					x2 = (x2 * 205) >> 11
				} else {
					x2 /= 10
				}
				bytes[j] = byte(bit) + '0'
				j++
				if x2 == 0 {
					break
				}
			}
			bytes[j] = '\n'
			j++
		}
	}
	//reverse
	upto := j
	j -= 2
	i = 0
	for ; i < j; {
		bytes[i], bytes[j] = bytes[j], bytes[i]
		i++
		j--
	}
	//write
	os.Stdout.Write(bytes[:upto])
}