---
id: cpp-conditions
title: "C++ If ... Else"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["if statement", "lowercase if", "C++ 조건문"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.85
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["cpp", "programming-language", "w3schools", "conditions", "if-statement"]
raw_sources: ["https://www.w3schools.com/cpp/cpp_conditions.asp"]
applied_in: []
github_commit: ""
---

# [[CPP If ... Else]]

## 🎯 한 줄 통찰 (One-line insight)
Every rule from C's `if` chapter carries over verbatim — lowercase-only `if` (uppercase `If`/`IF` errors), the same six comparison operators, and the same bool-variable-for-readability pattern — meaning C++'s conditional syntax is a direct, unmodified continuation of C's, with the only visible difference being `cout <<` replacing `printf()` inside the branches. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Six comparison conditions** — `<`, `<=`, `>`, `>=`, `==`, `!=`, identical to C. [S1]
- **Four conditional constructs** — `if`, `else`, `else if`, `switch` — same set as C. [S1]
- **Case-sensitive keyword** — `if` must be lowercase; `If`/`IF` produce an error. [S1]
- **Boolean-variable readability pattern** — storing a comparison's result in a `bool` variable before using it in `if` improves readability for complex/reused conditions. [S1]

## 📖 세부 내용 (Details)
- Basic if with variables: `int x = 20; int y = 18; if (x > y) { cout << "x is greater than y"; }`. [S1]
- Using a boolean variable to hold the condition: `bool isGreater = x > y; if (isGreater) { cout << "x is greater than y"; }`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- 현재까지 발견된 모순 사항 없음 (No contradictions found in available sources). C 챕터와 동일한 규칙임이 확인됨.

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 복잡하거나 재사용되는 조건을 bool 변수에 미리 담아두는 패턴이 가독성 있는 조건문 작성의 실전 관행이다. [S1]

## 💻 코드 패턴 (Code patterns)
Storing a condition in a readable boolean variable before using it in an if statement (C++):
```cpp
int x = 20;
int y = 18;
bool isGreater = x > y;
if (isGreater) {
  cout << "x is greater than y";
}
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.85
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[C++ Tutorial]]
- **관련 개념:** [[CPP Booleans RealLife]], [[CPP Conditions Else]], [[C Conditions]]
- **참조 맥락:** 조건문 섹션 첫 챕터 — else 문(Conditions Else) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — C++ If ... Else — https://www.w3schools.com/cpp/cpp_conditions.asp

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