84 lines
1.5 KiB
C++
84 lines
1.5 KiB
C++
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#include <fstream>
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#include <iostream>
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#include <set>
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#include <sstream>
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#include <string>
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#include <vector>
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int main()
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{
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std::ifstream ifs("data.txt");
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if(!ifs.is_open())
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{
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std::cerr << "Missing data.txt." << std::endl;
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return -1;
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}
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unsigned long total = 0;
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unsigned long total_pt2 = 0;
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for(std::string line; std::getline(ifs, line); )
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{
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if(line == "")
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continue;
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std::istringstream input(line);
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long *last = nullptr;
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bool *increasing = nullptr;
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bool safe = true;
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for(std::string value; std::getline(input, value, ' '); )
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{
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long current;
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// Get the value:
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try {
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current = std::atoi(value.c_str());
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} catch (const std::exception &e) {
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break;
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}
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// See if it's the first value:
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if(!last)
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{
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last = new long(current);
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continue;
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}
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// See if it's the second value:
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if(!increasing)
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{
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increasing = new bool(current > *last);
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}
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auto diff = current - *last;
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if(*increasing &&
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(diff < 1 || diff > 3))
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{
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safe = false;
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break;
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}
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if(!*increasing &&
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(diff < -3 || diff > -1))
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{
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safe = false;
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break;
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}
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if(last)
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*last = current;
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}
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if(increasing && last // actually made it through at least 2 values
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&& safe)
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total++;
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if(increasing)
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delete increasing, increasing = nullptr;
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if(last)
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delete last, last = nullptr;
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}
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std::cout << " Total: " << total << std::endl;
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std::cout << "PT2 Total: " << total_pt2 << std::endl;
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return 0;
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}
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