62 lines
2.0 KiB
C++
62 lines
2.0 KiB
C++
#include <fmt/format.h>
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#include <QCoreApplication>
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#include <QFile>
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#include <vector>
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#include <mergesort.h>
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/*
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Create a simple sorting application that uses the mergesort algorithm to sort a
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large collection (e.g., 10^7 ) of 32-bit integers. The input data and output results
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should be stored in files, and the I/O operations should be considered a
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sequential part of the application. Mergesort is an algorithm that is considered
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appropriate for parallel execution, although it cannot be equally divided between
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an arbitrary number of processors, as Amdahl’s and Gustafson-Barsis’ laws
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require.
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Assuming that this equal division is possible, estimate α, i.e., the part of the
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program that can be parallelized, by using a profiler like gprof or valgrind to
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measure the duration of mergesort’s execution relative to the overall execution
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time. Use this number to estimate the predicted speedup for your program.
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Does α depend on the size of the input? If it does, how should you modify
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your predictions and their graphical illustration?
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*/
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int main(int argc, char *argv[]) {
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QFile file("dataset.dat");
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if(!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
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fmt::print("Could not open file");
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return 0;
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}
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fmt::print("Opened file {} sucessfully!\n", file.fileName().toStdString());
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std::vector<int32_t> dataset;
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int counter = 0;
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while(!file.atEnd()) {
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dataset.emplace_back(file.readLine().toInt());
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}
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fmt::print("Read {} values from {}\n", dataset.size(), file.fileName().toStdString());
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algo::mergesort(dataset.begin(), dataset.end(), [](int32_t a, int32_t b) {
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return (a>b);
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});
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QFile outfile("dataset-sorted.dat");
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if(!outfile.open(QIODevice::WriteOnly | QIODevice::Text)) {
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fmt::print("Error! Could not create output file");
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}
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for(auto &val : dataset) {
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outfile.write(fmt::format("{}\n", val).c_str());
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}
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file.close();
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outfile.flush();
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outfile.close();
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return 0;
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}
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