37 lines
762 B
Text
37 lines
762 B
Text
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fn memoize(f) {
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let map = {};
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return fn(x) {
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if has(map, x) {
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return map[x];
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} else {
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let result = f(x);
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map[x] = result;
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return result;
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}
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};
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}
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fn fib(n) {
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if n <= 1 {
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return n;
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} else {
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return fib(n-1) + fib(n-2);
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}
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}
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for n: [10,20,25] {
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let start_time = time();
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let result = fib(n);
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let elapsed = time() - start_time;
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println("time for fib(" + str(n) + ")=" + str(result) + ": " + str(elapsed));
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}
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let fib = memoize(fib);
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for n: [10,20,25] {
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let start_time = time();
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let result = fib(n);
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let elapsed = time() - start_time;
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println("time for memoized fib(" + str(n) + ")=" + str(result) + ": " + str(elapsed));
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}
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