2nd/10_Wiki/Dev/Topic_C/C_Conditions_ElseIf.md

id, title, category, status, verification_status, canonical_id, aliases, duplicate_of, source_trust_level, confidence_score, created_at, updated_at, review_reason, merge_history, tags, raw_sources, applied_in, github_commit

id	title	category	status	verification_status	canonical_id	aliases	duplicate_of	source_trust_level	confidence_score	created_at	updated_at	review_reason	merge_history	tags	raw_sources	applied_in	github_commit
c-conditions-elseif	C Else If	Programming_Language	draft	conceptual		else if chain top to bottom evaluation C else if 문		B	0.85	2026-07-04	2026-07-04			c programming-language w3schools conditions else-if	https://www.w3schools.com/c/c_conditions_elseif.php

C Else If

🎯 한 줄 통찰 (One-line insight)

Conditions in an if/else-if chain are checked strictly top-to-bottom and STOP at the first true match — the source's time example explicitly notes "as soon as one condition is true, its block of code runs, and the rest are skipped," meaning even if a later condition would ALSO be true, only the FIRST matching branch ever executes; chain ORDER therefore determines behavior, not just correctness of each individual condition. [S1]

🧠 핵심 개념 (Core concepts)

• else if — tests a new condition only if the preceding condition(s) were false; can be chained multiple times. [S1]
• First-match-wins evaluation — conditions are checked top to bottom; the FIRST true condition's block runs and all subsequent conditions in the chain are skipped, even if they'd also evaluate true. [S1]
• Boolean-variable chaining — each condition in the chain can be pre-computed into a descriptively-named bool (isMorning, isDay) for readability. [S1]

📖 세부 내용 (Details)

• Time-of-day chain: int time = 16; if (time < 12) { printf("Good morning."); } else if (time < 18) { printf("Good day."); } else { printf("Good evening."); } // Outputs "Good day." — the first condition (time < 12) is false, the second (time < 18) is true, so only "Good day." prints. [S1]
• Same chain with named booleans: bool isMorning = time < 12; bool isDay = time < 18; if (isMorning) {...} else if (isDay) {...} else {...}. [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

• 첫 번째로 참인 조건만 실행됨: 체인 내 여러 조건이 이론상 동시에 참일 수 있어도, 위에서부터 먼저 참으로 판정된 조건의 블록만 실행되고 나머지는 건너뛴다는 점이 명시적으로 강조됨. [S1]

🛠️ 적용 사례 (Applied in summary)

현재 발견된 실제 적용 사례가 없습니다 — 시간대에 따라 아침/낮/저녁 인사를 구분하는 것이 else if 체인의 대표적인 실전 활용 예시다. [S1]

💻 코드 패턴 (Code patterns)

Chained else-if conditions evaluated top-to-bottom, stopping at the first match (C):

int time = 16;
if (time < 12) {
  printf("Good morning.");
} else if (time < 18) {
  printf("Good day.");
} else {
  printf("Good evening.");
}
// Outputs "Good day."

✅ 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: C Conditions Else, C Conditions Short Hand
• 참조 맥락: else if 체인 — 삼항 연산자(Conditions Short Hand) 챕터로 이어짐.

📚 출처 (Sources)

• [S1] W3Schools — C Else If — https://www.w3schools.com/c/c_conditions_elseif.php

📝 변경 이력 (Change history)

• 2026-07-04: Initial draft synthesized from the W3Schools "C Else If" page (Astra wiki-curation, P-Reinforce v3.1 format).