---
id: cpp-structs
title: "C++ Structures (struct)"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["named structures", "anonymous struct", "C++ 구조체"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.87
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["cpp", "programming-language", "w3schools", "structs"]
raw_sources: ["https://www.w3schools.com/cpp/cpp_structs.asp"]
applied_in: []
github_commit: ""
---

# [[CPP Structures (struct)]]

## 🎯 한 줄 통찰 (One-line insight)
Once a C++ struct is given a NAME (`struct car {...};`), that name alone becomes a usable data type — `car myCar1;` needs NO `struct` keyword before it — a direct contrast to C, where `struct car myCar1;` always requires the `struct` keyword UNLESS a separate `typedef` is used; meaning C++ eliminated an entire chapter's worth of C's typedef-with-struct workaround by making named structs behave as first-class types automatically. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Structure (`struct`)** — groups multiple MIXED-type variables ("members") into one unit; unlike C, members can include `string` directly. [S1]
- **Anonymous struct + variable in one declaration** — `struct { int myNum; string myString; } myStructure;` declares the type AND the variable together, with no reusable name. [S1]
- **Multiple variables of one anonymous struct** — `struct {...} myStruct1, myStruct2, myStruct3;` — comma-separated. [S1]
- **Named structs behave as data types with NO `struct` prefix needed** — `struct car {...}; car myCar1;` — unlike C, which always requires writing `struct car myCar1;` unless `typedef` is used. [S1]
- **Dot syntax (`.`)** — accesses/assigns individual members, same as C. [S1]

## 📖 세부 내용 (Details)
- Anonymous struct with a single variable: `struct { int myNum; string myString; } myStructure; myStructure.myNum = 1; myStructure.myString = "Hello World!";`. [S1]
- Named struct usable as a type with no `struct` keyword at the use site: `struct car { string brand; string model; int year; }; car myCar1; myCar1.brand = "BMW";`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- **이름 붙은 구조체는 struct 키워드 없이 타입처럼 사용 가능**: C에서는 typedef 없이는 항상 struct car myCar1;처럼 struct를 붙여야 했지만, C++에서는 struct car {...}; 선언 후 car myCar1;만으로 충분하다는 점이 명시적으로 확인됨 — C의 typedef-with-struct 챕터가 해결하던 문제를 C++는 언어 차원에서 이미 해결한 셈. [S1]

## 🛠️ 적용 사례 (Applied in summary)
Car 구조체 하나로 BMW와 Ford 두 대의 서로 다른 자동차 정보를 저장하는 예제가 원문에서 직접 실전 활용 사례로 제시됨(하나의 named struct, 여러 인스턴스). [S1]

## 💻 코드 패턴 (Code patterns)
A named struct used directly as a type, with no "struct" keyword needed at the declaration site (C++):
```cpp
struct car {
  string brand;
  string model;
  int year;
};
int main() {
  car myCar1;  // no "struct" prefix needed
  myCar1.brand = "BMW";
  myCar1.model = "X5";
  myCar1.year = 1999;
  return 0;
}
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.87
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[C++ Tutorial]]
- **관련 개념:** [[CPP Arrays RealLife]], [[CPP Enum]], [[C Structs]], [[C Typedef]]
- **참조 맥락:** 구조체 및 열거형 섹션 첫 챕터 — 열거형(Enum) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — C++ Structures (struct) — https://www.w3schools.com/cpp/cpp_structs.asp

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "C++ Structures (struct)" page (Astra wiki-curation, P-Reinforce v3.1 format).