Update 2021 sources to pass clang-tidy

2021/puzzle-01-02.cc

@@ -2,24 +2,25 @@
 // Created by Matthew Gretton-Dann on 01/12/2021.
 //
 
+#include <cassert>
 #include <cstdlib>
 #include <iostream>
 #include <limits>
 #include <string>
 #include <vector>
 
-int main(void)
+auto main() -> int
 {
-  std::vector<unsigned long> nums;
+  std::vector<std::uint64_t> nums;
   unsigned incrs{0};
   std::string line;
   while (std::getline(std::cin, line)) {
     nums.push_back(std::stoul(line));
   }
   assert(nums.size() >= 3);
-  unsigned long prev{std::numeric_limits<unsigned long>::max()};
+  std::uint64_t prev{std::numeric_limits<std::uint64_t>::max()};
   for (std::size_t pos = 0; pos <= nums.size() - 3; ++pos) {
-    unsigned long current{0};
+    std::uint64_t current{0};
     for (std::size_t i = pos + 0; i < pos + 3; ++i) {
       current += nums[i];
     }