go指南练习题 练习:切片 https://tour.go-zh.org/moretypes/18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 package main import ( "math" "golang.org/x/tour/pic" ) func Pic(dx, dy int) [][]uint8 { pic := make([][]uint8, dy) for y := 0; y < dy; y++ { pic[y] = make([]uint8, dx) for x := 0; x