2nd/10_Wiki/Dev/Topic_CPP/CPP_Arrays_Loop.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
cpp-arrays-loop	C++ Arrays and Loops	Programming_Language	draft	conceptual		loop through array foreach loop arrays C++ 배열 반복문		B	0.84	2026-07-04	2026-07-04			cpp programming-language w3schools arrays loops foreach	https://www.w3schools.com/cpp/cpp_arrays_loop.asp

CPP Arrays and Loops

🎯 한 줄 통찰 (One-line insight)

The for-each loop's element type must match the array's element type EXACTLY — for (int num : myNumbers) for an int array, for (string car : cars) for a string array — meaning unlike the traditional indexed loop (which works identically regardless of array type since it only manipulates an integer index), the for-each loop's syntax itself changes shape depending on what the array stores. [S1]

🧠 핵심 개념 (Core concepts)

• Traditional indexed loop — for (int i = 0; i < size; i++) { arr[i] ... } works the same regardless of array element type. [S1]
• For-each loop (C++11+) — for (type var : arrayName), used EXCLUSIVELY for looping through elements in an array or other data structures (vectors, lists). [S1]
• Type-matched for-each declaration — the loop variable's declared type must match the array's element type (int for an int array, string for a string array). [S1]

📖 세부 내용 (Details)

• Indexed loop with both index and value: for (int i = 0; i < 5; i++) { cout << i << " = " << cars[i] << "\n"; }. [S1]
• For-each loop over integers: for (int num : myNumbers) { cout << num << "\n"; }. [S1]
• For-each loop over strings: for (string car : cars) { cout << car << "\n"; }. [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

• for-each 루프는 배열 타입에 맞춰 변수 타입도 바뀜: 인덱스 기반 루프는 배열 타입과 무관하게 항상 int i로 동일하지만, for-each 루프는 int 배열엔 int, string 배열엔 string으로 변수 타입을 맞춰야 한다는 구문상 차이가 확인됨. [S1]

🛠️ 적용 사례 (Applied in summary)

현재 발견된 실제 적용 사례가 없습니다 — 인덱스와 값을 함께 출력하는 패턴이 배열 내 위치 정보가 필요한 실전 상황에서 인덱스 기반 루프의 활용 근거가 된다. [S1]

💻 코드 패턴 (Code patterns)

The for-each loop variable type matching the array's element type (C++):

string cars[5] = {"Volvo", "BMW", "Ford", "Mazda", "Tesla"};
for (string car : cars) {
  cout << car << "\n";
}

✅ 검증 상태 및 신뢰도

• 상태: draft
• 검증 단계: conceptual
• 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
• 신뢰 점수: 0.84
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: C++ Tutorial
• 관련 개념: CPP Arrays Size, CPP Arrays Multi, CPP For Loop Foreach
• 참조 맥락: 배열 반복문 — 다차원 배열(Arrays Multi) 챕터로 이어짐.

📚 출처 (Sources)

• [S1] W3Schools — C++ Arrays and Loops — https://www.w3schools.com/cpp/cpp_arrays_loop.asp

📝 변경 이력 (Change history)

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