54 lines
1.1 KiB
Swift
54 lines
1.1 KiB
Swift
import Foundation
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func isPrime(_ n: Int) -> Bool {
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if n < 2 {
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return false
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}
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if n % 2 == 0 {
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return n == 2
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}
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if n % 3 == 0 {
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return n == 3
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}
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var p = 5
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while p * p <= n {
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if n % p == 0 {
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return false
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}
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p += 2
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if n % p == 0 {
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return false
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}
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p += 4
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}
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return true
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}
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func isMagnanimous(_ n: Int) -> Bool {
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var p = 10;
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while n >= p {
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if !isPrime(n % p + n / p) {
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return false
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}
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p *= 10
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}
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return true
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}
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let m = (0...).lazy.filter{isMagnanimous($0)}.prefix(400);
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print("First 45 magnanimous numbers:");
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for (i, n) in m.prefix(45).enumerated() {
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if i > 0 && i % 15 == 0 {
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print()
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}
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print(String(format: "%3d", n), terminator: " ")
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}
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print("\n\n241st through 250th magnanimous numbers:");
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for n in m.dropFirst(240).prefix(10) {
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print(n, terminator: " ")
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}
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print("\n\n391st through 400th magnanimous numbers:");
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for n in m.dropFirst(390) {
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print(n, terminator: " ")
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}
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print()
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