package main

import (
	"bufio"
	"log"
	"os"
)

// readlines reads lines from stdin.
// it returns them as an array of strings
func readlines() []string {
	lines := []string{}

	scanner := bufio.NewScanner(os.Stdin)
	for scanner.Scan() {
		lines = append(lines, scanner.Text())
	}

	if err := scanner.Err(); err != nil {
		log.Fatal(err)
	}

	return lines
}

// parselines stores each image into an images struct
func parselines(lines []string) {
	addImage := func(i int) int {
		image := newImg()
		for ; i < len(lines); i++ {
			if len(lines[i]) == 0 {
				break
			}
			image.raw = append(image.raw, lines[i])
		}
		images.img = append(images.img, image)
		return i
	}

	images = newImages()

	for i := 0; i < len(lines); i++ {
		next := addImage(i)
		i = next
	}
}

// numDiffs returns the number of difference between two strings
func numDiffs(a, b string) int {
	diff := 0
	for i := range a {
		if a[i] != b[i] {
			diff++
		}
	}
	return diff
}