70 lines
1.0 KiB
Go
70 lines
1.0 KiB
Go
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package pe27
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import (
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"fmt"
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"math"
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)
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type Params struct {
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A int
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B int
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N int
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}
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func is_prime(x int) bool {
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if x < 0 {
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x = -x
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}
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if x == 0 || x == 1 {
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return false
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}
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if x == 2 {
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return true
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}
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for i := 2; float64(i) <= math.Sqrt(float64(x)); i++ {
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if x%i == 0 {
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return false
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}
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}
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return true
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}
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func count_primes(a, b int, c chan Params) {
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num_primes := 0
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for n := 0; ; n++ {
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ans := n*n + a*n + b
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if !is_prime(ans) {
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break
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} else {
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num_primes++
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}
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}
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c <- Params{a, b, num_primes}
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}
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func Solve(_ []string) {
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c := make(chan Params, 3999999)
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var a, b int
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for a = -999; a < 1000; a++ {
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for b = -1000; b < 1001; b++ {
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go count_primes(a, b, c)
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}
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}
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max_a, max_b, max := 0, 0, 0
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for i := 0; i < 3999999; i++ {
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arr := <-c
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if arr.N > max {
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max_a = arr.A
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max_b = arr.B
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max = arr.N
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}
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}
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fmt.Println("A:", max_a, "B:", max_b, "Num Primes:", max, "A * B:", max_a*max_b)
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/*
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for i := 0; i < 100; i++ {
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fmt.Println("i:", i, "is prime:", is_prime(i))
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}
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*/
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}
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