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discard """
matrix: "--mm:refc"
output: "500"
"""
import threadpool, sequtils
{.experimental: "parallel".}
proc linearFind(a: openArray[int]; x, offset: int): int =
for i, y in a:
if y == x: return i+offset
result = -1
proc parFind(a: seq[int]; x: int): int =
var results: array[4, int]
parallel:
if a.len >= 4:
let chunk = a.len div 4
results[0] = spawn linearFind(a[0 ..< chunk], x, 0)
results[1] = spawn linearFind(a[chunk ..< chunk*2], x, chunk)
results[2] = spawn linearFind(a[chunk*2 ..< chunk*3], x, chunk*2)
results[3] = spawn linearFind(a[chunk*3 ..< a.len], x, chunk*3)
result = max(results)
let data = toSeq(0..1000)
echo parFind(data, 500)
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