3rd day, 1st challenge

3rd_day/1/main.cpp

@@ -0,0 +1,53 @@
+#include <fstream>
+#include <iostream>
+#include <string>
+#include <vector>
+
+using namespace std;
+
+vector<string> get_input(const string FILE_NAME) {
+  ifstream file = ifstream(FILE_NAME);
+  string s;
+  vector<string> input;
+  while (getline(file, s)) {
+    input.push_back(s);
+  }
+  return input;
+}
+
+int find_highest_joltage(string bank) {
+  int number;
+  int first_highest_num = 0;
+  int second_highest_num = 0;
+  int highest_pos;
+
+  for (int i = 0; i < bank.length() - 1; i++) {
+    number = stoi(bank.substr(i, 1));
+    if (number > first_highest_num) {
+      first_highest_num = number;
+      highest_pos = i;
+    }
+  }
+
+  for (int i = highest_pos + 1; i < bank.length(); i++) {
+    number = stoi(bank.substr(i, 1));
+    if (number > second_highest_num) {
+      second_highest_num = number;
+    }
+  }
+  string result = to_string(first_highest_num) + to_string(second_highest_num);
+
+  return stoi(result);
+}
+
+int main() {
+  const string FILE_NAME = "input.txt";
+  vector<string> banks = get_input(FILE_NAME);
+  int sum = 0;
+  for (string bank : banks) {
+    int highest_joltage = find_highest_joltage(bank);
+    cout << "Highest joltage found: " << highest_joltage << endl;
+    sum += highest_joltage;
+  }
+  cout << "Sum of all the joltage: " << sum << endl;
+}