auto ps = generate(n, randpair); auto rs = map([](pair p){return p.x*p.x+p.y*p.y},ps); auto ios = map([](double r2){return r2 <= 1;}, rs); double pi = reduce(std::plus<double>(), ios) /size*4;

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#processor

Exe

cution

Tim

e (s

)

naïve parallelsequentialoptimized parallel

On a workstation with two Intel®Xeon® X5550 (8 cores in total,

without hyper-threading), 12GB memory, and Linux 2.6.31.