1 files changed, 82 insertions, 0 deletions

diff --git a/2023/src/day01.cpp b/2023/src/day01.cpp
new file mode 100644
index 0000000..ff357bc
--- /dev/null
+++ b/2023/src/day01.cpp
@@ -0,0 +1,82 @@
+#include <algorithm>
+#include <fstream>
+#include <iostream>
+#include <map>
+#include <string>
+#include <vector>
+using namespace std;
+
+void
+part1()
+{
+        string  digits{ "0123456789" };
+        fstream input{ "data/day01.txt" };
+
+        int sum = 0;
+        for ( string line; input >> line; ) {
+                auto first = find_first_of(begin(line), end(line), begin(digits), end(digits));
+                auto last  = find_first_of(rbegin(line), rend(line), begin(digits), end(digits));
+
+                auto value = (*first - '0') * 10 + (*last - '0');
+
+                sum += value;
+        }
+        cout << sum << endl;
+}
+
+void
+part2()
+{
+        map<string, int> map{
+                { "0", 0 },
+                { "1", 1 },
+                { "2", 2 },
+                { "3", 3 },
+                { "4", 4 },
+                { "5", 5 },
+                { "6", 6 },
+                { "7", 7 },
+                { "8", 8 },
+                { "9", 9 },
+                { "one", 1 },
+                { "two", 2 },
+                { "three", 3 },
+                { "four", 4 },
+                { "five", 5 },
+                { "six", 6 },
+                { "seven", 7 },
+                { "eight", 8 },
+                { "nine", 9 },
+        };
+
+        fstream input{ "data/day01.txt" };
+
+        auto sum = 0;
+        for ( string line; input >> line; ) {
+                string      sub;
+                vector<int> digits;
+
+                for ( auto ch: line ) {
+                        sub += ch;
+
+                        for ( const auto& word: map ) {
+                                if ( sub.ends_with(word.first) ) {
+                                        digits.push_back(word.second);
+                                }
+                        }
+                }
+
+                auto first = digits.front();
+                auto last  = digits.back();
+
+                sum += (first * 10) + last;
+        }
+        cout << sum << endl;
+}
+
+int
+main()
+{
+        part1();
+        part2();
+}