   var c = 0
   for _ in 1...n*10000 {
     let mapped = numbers.lazy.map { $0 &+ 5 }
-    c += mapped.reduce(0, &+)
+    c = c &+ mapped.reduce(0, &+)
   }
   check(c != 0)
 }


  var c: UInt64 = 0
  for _ in 1...n*100 {
    c += s.utf8.map { UInt64($0 &+ 5) }.reduce(0, &+)
  }
  check(c != 0)
}

  var c = 0
  for _ in 1...n*1_000 {
    let mapped = numbers.map { $0 &+ 5 }
    c = c &+ mapped.reduce(0, &+)
  }
  check(c != 0)
}
