Two sum: Difference between revisions

=={{header|Wren}}==

<lang ecmascript>var twosum = Fn.new { |a, n|

var c = a.count

if (c < 2) return []

for (i in 0...c-1) {

for (j in i+1...c) {

var s = a[i] + a[j]

if (s == n) return [i, j]

if (s > n) break

}

}

return []

}

var a = [0, 2, 11, 19, 90]

System.print("Numbers: %(a)\n")

for (n in [21, 25, 90]) {

var pair = twosum.call(a, n)

if (pair.count == 2) {

System.print("Indices: %(pair) sum to %(n) (%(a[pair[0]]) + %(a[pair[1]]) = %(n))")

} else {

System.print("No pairs of the above numbers sum to %(n).")

}

System.print()

}</lang>

{{out}}

<pre>

Numbers: [0, 2, 11, 19, 90]

Indices: [1, 3] sum to 21 (2 + 19 = 21)

No pairs of the above numbers sum to 25.

Indices: [0, 4] sum to 90 (0 + 90 = 90)

</pre>