forked from danmax/aoc
47 lines
1.1 KiB
C++
47 lines
1.1 KiB
C++
#include <iostream>
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#include <fstream>
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#include <vector>
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#include <algorithm>
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#include <cmath>
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#include <chrono>
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int main() {
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std::vector<int> x;
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std::vector<int> y;
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int l, r;
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long t = 0;
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long t2 = 0;
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int c = 0;
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std::chrono::steady_clock::time_point begin = std::chrono::steady_clock::now();
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std::ifstream f("b");
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while (f >> l >> r) {
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x.push_back(l);
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y.push_back(r);
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}
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std::sort(x.begin(), x.end());
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std::sort(y.begin(), y.end());
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for (size_t i = 0; i < 4000000; i++) {
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t += std::abs(x[i] - y[i]);
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}
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auto p = y.begin();
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for (size_t i = 0; i < 4000000; i++) {
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auto b = std::lower_bound(p, y.end(), x[i]);
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auto u = std::upper_bound(p, y.end(), x[i]);
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int c = u - b;
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t2 += x[i] * c;
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p = b;
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}
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std::chrono::steady_clock::time_point end = std::chrono::steady_clock::now();
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std::cout << "Part 1: " << t << "\nPart 2: " << t2 << "\n";
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std::cout << "Time difference = " << std::chrono::duration_cast<std::chrono::microseconds>(end - begin).count() << " microseconds" << std::endl;
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return 0;
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}
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