29 lines
758 B
C++
29 lines
758 B
C++
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/* Compile using `clang day6.cpp -o day6 -lstdc++ -std=c++11` */
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#include <string>
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#include <fstream>
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#include <iostream>
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#include <set>
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int find_marker(std::string input, int size) {
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auto start = input.begin();
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while (start + size != input.end()) {
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auto group = std::set<char>(start, start + size);
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if (group.size() == size) {
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return start - input.begin() + size;
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}
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start++;
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}
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return -1;
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}
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int main() {
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std::string input;
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std::ifstream file("day6.input");
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std::getline(file, input);
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std::cout << "Part 1: First marker after " << find_marker(input, 4) << " characters\n";
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std::cout << "Part 2: First marker after " << find_marker(input, 14) << " characters\n";
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}
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