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#include <fstream>
#include <iostream>
#include <numeric>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
string
read_file(string_view filename)
{
fstream input{ filename };
return { istreambuf_iterator<char>{ input }, {} };
}
vector<string>
split(string_view line, string_view delimiter)
{
string::size_type pos_start = 0;
string::size_type pos_end = 0;
vector<string> result;
while ( (pos_end = line.find(delimiter, pos_start)) != string::npos ) {
result.emplace_back(line.substr(pos_start, pos_end - pos_start));
pos_start = pos_end + delimiter.length();
}
if ( pos_start != line.size() ) {
result.emplace_back(line.substr(pos_start));
}
return result;
}
vector<long>
split(const string& line)
{
stringstream input{ line };
return { istream_iterator<long>(input), {} };
}
void
part1(const vector<string>& parts)
{
long max_so_far = 0;
for ( const auto& part: parts ) {
const auto nums = split(part);
max_so_far = max(accumulate(begin(nums), end(nums), 0L), max_so_far);
}
cout << max_so_far << endl;
}
void
part2(const vector<string>& parts)
{
vector<long> all;
for ( const auto& part: parts ) {
const auto nums = split(part);
all.emplace_back(accumulate(begin(nums), end(nums), 0L));
}
sort(begin(all), end(all), greater<>());
cout << all[0] + all[1] + all[2] << endl;
}
int
main()
{
const auto line = read_file("data/day01.txt");
const auto parts = split(line, "\n\n");
part1(parts);
part2(parts);
}
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