yusuke024/aina.swift

## aina.swift
#!/usr/bin/env swift

// swift aina.swift <n>

import Foundation

func p(_ n: Int) -> [String] {
  if n == 0 { return ["A"] }

  let p1 = [" A ", "A A", "AAA", "A A", "A A"]

  var result: [String] = []
  let prev = p(n-1) // Recursively get result of P(n-1).
  for line in prev {
    for p1l in p1 { // For each line in P(1)
      var l = ""
      for c in line { // Iterate each character in previous result
        if c == " " { l += "   " } // 3 spaces. Because P(1) is 3-space wide.
        if c == "A" { l += p1l }
      }
      result.append(l)
    }
  }
  return result
}

guard CommandLine.arguments.count == 2, let n = Int(CommandLine.arguments[1]) else {
  fatalError("Need one argument (Int)")
}

print(p(n).joined(separator: "\n"))
	#!/usr/bin/env swift

	// swift aina.swift <n>

	import Foundation

	func p(_ n: Int) -> [String] {
	if n == 0 { return ["A"] }

	let p1 = [" A ", "A A", "AAA", "A A", "A A"]

	var result: [String] = []
	let prev = p(n-1) // Recursively get result of P(n-1).
	for line in prev {
	for p1l in p1 { // For each line in P(1)
	var l = ""
	for c in line { // Iterate each character in previous result
	if c == " " { l += " " } // 3 spaces. Because P(1) is 3-space wide.
	if c == "A" { l += p1l }
	}
	result.append(l)
	}
	}
	return result
	}

	guard CommandLine.arguments.count == 2, let n = Int(CommandLine.arguments[1]) else {
	fatalError("Need one argument (Int)")
	}

	print(p(n).joined(separator: "\n"))