Create andyli.cpp

src/群友提交/第二题/andyli.cpp

@@ -0,0 +1,29 @@
+#include <format>
+#include <iostream>
+#include <string_view>
+#include <string>
+
+namespace impl {
+    struct Helper {
+        const std::string_view s;
+        Helper(const char* s, std::size_t len): s(s, len) {}
+        template <typename... Args>
+        std::string operator()(Args&&... args) const {
+            return std::vformat(s, std::make_format_args(std::forward<Args>(args)...));
+        }
+    };
+} // namespace impl
+impl::Helper operator""_f(const char* s, std::size_t len) noexcept {
+    return {s, len};
+}
+
+int main() {
+    std::cout << "乐 :{} *\n"_f(5);
+    std::cout << "乐 :{0} {0} *\n"_f(5);
+    std::cout << "乐 :{:b} *\n"_f(0b01010101);
+    std::cout << "{:*<10}"_f("卢瑟");
+    std::cout << '\n';
+    int n{};
+    std::cin >> n;
+    std::cout << "π：{:.{}f}\n"_f(std::numbers::pi_v<double>, n);
+}