- Added guest contributions by Humberto Massa.

1 files changed, 25 insertions, 0 deletions

diff --git a/challenge-180/massa/cpp/ch-1.cpp b/challenge-180/massa/cpp/ch-1.cpp
new file mode 100644
index 0000000000..f6e69de7f2
--- /dev/null
+++ b/challenge-180/massa/cpp/ch-1.cpp
@@ -0,0 +1,25 @@
+
+#include <span>
+#include <ranges>
+#include <iostream>
+#include <string_view>
+
+template <std::input_iterator It, std::sentinel_for<It> S>
+It first_unique(It begin, S end) {
+  for( auto it = begin; it != end; ++it )
+    if( std::find(begin, it, *it) == it && std::find(it+1, end, *it) == end )
+      return it;
+  return end;
+}
+
+auto first_unique(std::ranges::input_range auto range) {
+  return first_unique(begin(range), end(range));
+}
+
+int main(int argc, char **argv) {
+  for( std::string_view a: std::span { argv+1, argv+argc } ) {
+    auto u = first_unique(a);
+    std::cout << (u == std::end(a) ? -1 : u - std::begin(a)) << ' ' << a << '\n';
+  }
+}
+