docs(10_Wiki): 위키 구조 정리 — 언어 튜토리얼 카테고리 폴더 제거 + 신규 자산 동기화

Topic_CSS/Topic_HTML/Topic_JavaScript/Topic_Prompt/Topic_Comfyui 등 기존 카테고리 폴더를 정리하고, Topic_Graphic/Dev 등 신규 산출물과 Topics 내부 세션/메모리 기록을 동기화.
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+---
+id: java-numbers
+title: "Java Numbers"
+category: "Programming_Language"
+status: "draft"
+verification_status: "conceptual"
+canonical_id: ""
+aliases: ["byte short int long float double", "자바 숫자 타입"]
+duplicate_of: ""
+source_trust_level: "B"
+confidence_score: 0.9
+created_at: 2026-07-04
+updated_at: 2026-07-04
+review_reason: ""
+merge_history: []
+tags: ["java", "programming", "w3schools", "numbers", "int", "double"]
+raw_sources: ["https://www.w3schools.com/java/java_data_types_numbers.asp"]
+applied_in: []
+github_commit: ""
+---
+
+# [[Java Numbers]]
+
+## 🎯 한 줄 통찰 (One-line insight)
+`long` values need a trailing `L` and `float` values need a trailing `f` (double needs `d`, but it's optional since double is the default) — omitting these suffixes on large/decimal literals causes compile errors or silent precision loss. [S1]
+
+## 🧠 핵심 개념 (Core concepts)
+- **Integer types** — `byte`, `short`, `int` (preferred default for whole numbers), `long` (for values too large for int, requires `L` suffix). [S1]
+- **Floating point types** — `float` (requires `f` suffix, 6-7 decimal digit precision), `double` (15-16 digit precision, preferred for most calculations). [S1]
+- **Scientific notation** — `float f1 = 35e3f; double d1 = 12E4d;` uses `e`/`E` for powers of 10. [S1]
+
+## 🧩 추출된 패턴 (Extracted patterns)
+- **Literal suffix requirement scales with type size** — `L` for long, `f` for float, `d` for double (optional) — the suffix tells the compiler which literal type to use, since Java's default numeric literal types are `int` and `double`. [S1]
+- **double as the safe default for decimals** — the tutorial explicitly recommends double over float for most calculations due to its much higher precision. [S1]
+
+## 📖 세부 내용 (Details)
+- byte: `byte myNum = 100;` (range -128 to 127). [S1]
+- short: `short myNum = 5000;` (range -32768 to 32767). [S1]
+- int: `int myNum = 100000;` (preferred default). [S1]
+- long: `long myNum = 15000000000L;` (note the `L` suffix). [S1]
+- float: `float myNum = 5.75f;`. [S1]
+- double: `double myNum = 19.99d;`. [S1]
+- Scientific notation: `float f1 = 35e3f; double d1 = 12E4d;`. [S1]
+
+## ⚖️ 모순 및 업데이트 (Contradictions & updates)
+소스에서 모순되는 정보는 발견되지 않음.
+
+## 🛠️ 적용 사례 (Applied in summary)
+현재 발견된 실제 적용 사례가 없습니다 — Type Casting 챕터에서 이 숫자 타입들 간 자동/수동 변환이 다뤄진다. [S1]
+
+## 💻 코드 패턴 (Code patterns)
+Long and float literal suffixes (Java):
+```java
+long myNum = 15000000000L;
+float myFloat = 5.75f;
+double myDouble = 19.99d;  // d is optional (double is the default)
+```
+
+## ✅ 검증 상태 및 신뢰도
+- **상태:** draft
+- **검증 단계:** conceptual
+- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
+- **신뢰 점수:** 0.90
+- **중복 검사 결과:** 신규 생성 (New discovery)
+
+## 🔗 지식 그래프 (Knowledge Graph)
+- **상위/루트:** [[Java Tutorial]]
+- **관련 개념:** [[Java Data Types]], [[Java Type Casting]], [[Java Math]]
+- **참조 맥락:** 6개 숫자 타입의 상세 — 리터럴 접미사(L/f/d) 규칙이 핵심.
+
+## 📚 출처 (Sources)
+- [S1] W3Schools — Java Numbers — https://www.w3schools.com/java/java_data_types_numbers.asp
+
+## 📝 변경 이력 (Change history)
+- 2026-07-04: Initial draft synthesized from the W3Schools "Java Numbers" page (Astra wiki-curation, P-Reinforce v3.1 format).