node/deps/v8/test/mjsunit/greedy.js

// Copyright 2008 the V8 project authors. All rights reserved.
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// modification, are permitted provided that the following conditions are
// met:
//
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//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
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//       with the distribution.
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//
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// Flags: --gc-greedy

function IterativeFib(n) {
  var f0 = 0, f1 = 1;
  for (; n > 0; --n) {
    var f2 = f0 + f1;
    f0 = f1; f1 = f2;
  }
  return f0;
}

function RecursiveFib(n) {
  if (n <= 1) return n;
  return RecursiveFib(n - 1) + RecursiveFib(n - 2);
}

function Check(n, expected) {
  var i = IterativeFib(n);
  var r = RecursiveFib(n);
  assertEquals(i, expected);
  assertEquals(r, expected);
}

Check(0, 0);
Check(1, 1);
Check(2, 1);
Check(3, 1 + 1);
Check(4, 2 + 1);
Check(5, 3 + 2);
Check(10, 55);
Check(15, 610);
Check(20, 6765);
assertEquals(IterativeFib(75), 2111485077978050);