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// Copyright (C) 2015 Apple Inc. All rights reserved.
// 
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function benchmark() {
    var verbosity = 0;
    var numAircraft = 1000;
    var numFrames = 200;
    var expectedCollisions = 14484;
    var percentile = 95;

    var simulator = new Simulator(numAircraft);
    var detector = new CollisionDetector();
    var lastTime = currentTime();
    var results = [];
    for (var i = 0; i < numFrames; ++i) {
        var time = i / 10;
        
        var collisions = detector.handleNewFrame(simulator.simulate(time));
        
        var before = lastTime;
        var after = currentTime();
        lastTime = after;
        var result = {
            time: after - before,
            numCollisions: collisions.length
        };
        if (verbosity >= 2)
            result.collisions = collisions;
        results.push(result);
    }

    if (verbosity >= 1) {
        for (var i = 0; i < results.length; ++i) {
            var string = "Frame " + i + ": " + results[i].time + " ms.";
            if (results[i].numCollisions)
                string += " (" + results[i].numCollisions + " collisions.)";
            print(string);
            if (verbosity >= 2 && results[i].collisions.length)
                print("    Collisions: " + results[i].collisions);
        }
    }

    // Check results.
    var actualCollisions = 0;
    for (var i = 0; i < results.length; ++i)
        actualCollisions += results[i].numCollisions;
    if (actualCollisions != expectedCollisions) {
        throw new Error("Bad number of collisions: " + actualCollisions + " (expected " +
                        expectedCollisions + ")");
    }

    // Find the worst 5% 
    var times = [];
    for (var i = 0; i < results.length; ++i)
        times.push(results[i].time);
    
    return averageAbovePercentile(times, percentile);
}