ps.go

/*
*  palindromic squares generator
*
*/
package main

import (
    "bufio"
    "fmt"
    "os"
    "math/big"
    "strings"
)

const (
    path = "ps.txt"
)

var (
    file *os.File
    writer *bufio.Writer
    number *big.Int
)

func files() {
    var err error
    file, err = os.Create(path)
    if err != nil {
        fmt.Println(err)
    }
    writer = bufio.NewWriter(file)
}

func cleanup() {
    writer.Flush()
    var err error
    err = file.Close()
    if err != nil {
        fmt.Println(err)
    }
}

func generate() {
    number = big.NewInt(0)
    one := big.NewInt(1)
    for i := 0; i < 20000003; i++ {
        m0 := mirror(number)
        if m0 {
            // fmt.Println(number, m0)
            square := big.NewInt(0)
            square.Mul(number, number)
            m1 := mirror(square)
            if m1 {
                fmt.Println(number, square, m1)
                output(number.String(), square.String())
            }
        }
        number.Add(number, one)
    }
}

func mirror(n0 *big.Int) bool {
    // palindrome test
    s0 := n0.String()
    if len(s0) == 1 {
        return true
    }
    a0 := strings.Split(s0, "")
    b0 := true
    for i := 0; i < len(a0) / 2; i++ {
        if a0[i] != a0[len(a0)-1-i] {
            b0 = false
            break
        }
    }
    return b0
}

func output(n0 string, s0 string) {
    s1 := fmt.Sprintf("%s %s\n", n0, s0)
    writer.WriteString(s1)
}

func main() {
    files()
    defer cleanup()
    generate()
}