---
id: cpp-operators-arithmetic
title: "C++ Arithmetic Operators"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["integer division", "increment decrement", "C++ 산술 연산자"]
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", "operators", "arithmetic"]
raw_sources: ["https://www.w3schools.com/cpp/cpp_operators_arithmetic.asp"]
applied_in: []
github_commit: ""
---

# [[CPP Arithmetic Operators]]

## 🎯 한 줄 통찰 (One-line insight)
Integer division truncation carries over from C completely unchanged — `10 / 3` still yields `3` in C++, and the fix is identical too (use `double` operands: `10.0 / 3` gives `3.333...`) — confirming that C++'s arithmetic semantics for the basic numeric types are inherited from C wholesale, not just its syntax. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Seven core arithmetic operators** — `+`, `-`, `*`, `/`, `%` (modulus), `++` (increment), `--` (decrement) — identical set to C. [S1]
- **Integer division truncation** — dividing two `int`s always yields an `int`, discarding any decimal remainder; use `double` operands for a decimal result. [S1]
- **Increment/decrement round-trip** — incrementing then decrementing the same variable returns it to its original value. [S1]

## 📖 세부 내용 (Details)
- All seven operators demonstrated with chained cout output: `int x = 10; int y = 3; cout << (x + y) << "\n"; // 13 ... cout << (x % y) << "\n"; // 1`. [S1]
- Integer vs decimal division contrast: `int x = 10; int y = 3; cout << (x / y); // 3 (integer division)` versus `double a = 10.0; double b = 3.0; cout << (a / b); // 3.333...`. [S1]
- Real-life counting example: `int peopleInRoom = 0; peopleInRoom++; peopleInRoom++; peopleInRoom++; // 3 people enter cout << peopleInRoom; // 3` then `peopleInRoom--; // 2`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- **C와 완전히 동일한 정수 나눗셈 절삭**: int끼리 나누면 소수점이 버려진다는 점과 그 해결책(double 사용)이 C 챕터와 동일하게 확인됨. [S1]

## 🛠️ 적용 사례 (Applied in summary)
방에 들어오고 나가는 사람 수를 ++/--로 세는 카운터 예제가 원문에서 직접 실전 활용 사례로 제시됨(C 챕터와 동일한 예제). [S1]

## 💻 코드 패턴 (Code patterns)
Integer division truncates; use double operands for a decimal result (C++):
```cpp
int x = 10;
int y = 3;
cout << (x / y); // Integer division, result is 3

double a = 10.0;
double b = 3.0;
cout << (a / b); // Decimal division, result is 3.333...
```

## ✅ 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 Operators]], [[CPP Operators Assignment]], [[C Operators Arithmetic]]
- **참조 맥락:** 산술 연산자 — 대입 연산자(Operators Assignment) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — C++ Arithmetic Operators — https://www.w3schools.com/cpp/cpp_operators_arithmetic.asp

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