package main

import (
	"encoding/csv"
	"fmt"
	"log"
	"os"
	"strconv"
)

func main() {
	fmt.Println("Enter Number:")
	var number int
	_, err := fmt.Scanf("%d", &number)
	if err != nil {
		log.Fatal(err)
	}

	matrice := make([][]int, number+1)


	for i := 0; i <= number; i++ {
		matrice[i] = make([]int, number+1)
		for j := 0; j <= number; j++ {
			matrice[i][j] = (j * i) % number
		}
	}

	// Save it
	if err := csvExport(matrice); err != nil {
		log.Fatal(err)
	}

	// output it
	fmt.Print("\t")
	for i := 0; i <= number; i++ {
		fmt.Print(i, "\t")
	}
	fmt.Println()

	for rownumber, row := range matrice {
		fmt.Print(rownumber, "\t")
		for _, col := range row {
			fmt.Print(col, "\t")
		}
		fmt.Println()
	}

}

func csvExport(data [][]int) error {
	file, err := os.Create("result.csv")
	if err != nil {
		return err
	}
	defer file.Close()

	writer := csv.NewWriter(file)
	defer writer.Flush()

	//Prepare
	dataStrings := make([][]string, len(data))
	for in := range data {
		dataStrings[in] = make([]string, len(data[in]))
		for in2, val2 := range data[in] {
			dataStrings[in][in2] = strconv.Itoa(val2)
		}
	}

	for _, value := range dataStrings {
		if err := writer.Write(value); err != nil {
			return err // let's return errors if necessary, rather than having a one-size-fits-all error handler
		}
	}
	return nil
}