---
id: c-conditions-elseif
title: "C Else If"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["else if chain", "top to bottom evaluation", "C else if 문"]
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: ["c", "programming-language", "w3schools", "conditions", "else-if"]
raw_sources: ["https://www.w3schools.com/c/c_conditions_elseif.php"]
applied_in: []
github_commit: ""
---

# [[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):
```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).
