diff --git "a/Programmers/Level2/12981_\354\230\201\354\226\264_\353\201\235\353\247\220\354\236\207\352\270\260.js" "b/Programmers/Level2/12981_\354\230\201\354\226\264_\353\201\235\353\247\220\354\236\207\352\270\260.js"
new file mode 100644
index 0000000..c0de2c9
--- /dev/null
+++ "b/Programmers/Level2/12981_\354\230\201\354\226\264_\353\201\235\353\247\220\354\236\207\352\270\260.js"
@@ -0,0 +1,24 @@
+/* 
+⭐️ 문제 정보 ⭐️
+문제 : 12981 - 영어 끝말잇기
+레벨 : Level 2
+링크 : https://school.programmers.co.kr/learn/courses/30/lessons/12981
+*/
+
+// ANCHOR - 2025.12.05 풀이
+function solution(n, words) {
+  const wordSet = new Set();
+  wordSet.add(words[0]);
+
+  for (let cur = 1; cur < words.length; cur++) {
+    if (wordSet.has(words[cur]) || words[cur - 1].at(-1) !== words[cur].at(0)) {
+      const loser = (cur % n) + 1;
+      const round = parseInt(cur / n) + 1;
+      return [loser, round];
+    } else {
+      wordSet.add(words[cur]);
+    }
+  }
+
+  return [0, 0];
+}
diff --git "a/Programmers/Level2/42577_\354\240\204\355\231\224\353\262\210\355\230\270_\353\252\251\353\241\235.js" "b/Programmers/Level2/42577_\354\240\204\355\231\224\353\262\210\355\230\270_\353\252\251\353\241\235.js"
new file mode 100644
index 0000000..b20c774
--- /dev/null
+++ "b/Programmers/Level2/42577_\354\240\204\355\231\224\353\262\210\355\230\270_\353\252\251\353\241\235.js"
@@ -0,0 +1,25 @@
+/* 
+⭐️ 문제 정보 ⭐️
+문제 : 42577 - 전화번호 목록
+레벨 : Level 2
+링크 : https://school.programmers.co.kr/learn/courses/30/lessons/42577
+*/
+
+// ANCHOR - 2025.12.05 풀이
+function solution(phone_book) {
+  const numberSet = new Set();
+  for (const number of phone_book) {
+    // 같은 전화번호가 중복해서 들어있지 않으므로 끝번호를 제외한 부분문자열만 구해준다.
+    for (let len = 1; len < number.length; len++) {
+      numberSet.add(number.substr(0, len));
+    }
+  }
+
+  for (const number of phone_book) {
+    if (numberSet.has(number)) {
+      return false;
+    }
+  }
+
+  return true;
+}
diff --git a/Programmers/README.md b/Programmers/README.md
index 1864b6a..31cb66d 100644
--- a/Programmers/README.md
+++ b/Programmers/README.md
@@ -17,6 +17,7 @@
 | 12941 | 최솟값 만들기 | [12941_최솟값_만들기.js](Level2/12941_최솟값_만들기.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/12941) |
 | 12949 | 행렬의 곱셈 | [12949_행렬의_곱셈.js](Level2/12949_행렬의_곱셈.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/12949) |
 | 12973 | 짝지어 제거하기 | [12973_짝지어_제거하기.js](Level2/12973_짝지어_제거하기.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/12973) |
+| 12981 | 영어 끝말잇기 | [12981_영어_끝말잇기.js](Level2/12981_영어_끝말잇기.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/12981) |
 | 12985 | 예상 대진표 | [12985_예상_대진표.js](Level2/12985_예상_대진표.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/12985) |
 | 12987 | 숫자 게임 | [12987_숫자_게임.js](Level3/12987_숫자_게임.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/12987) |
 | 17677 | [1차] 뉴스 클러스터링 | [17677_[1차]_뉴스_클러스터링.js](Level2/17677_[1차]_뉴스_클러스터링.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/17677) |
@@ -26,6 +27,7 @@
 | 17686 | [3차] 파일명 정렬 | [17686_[3차]_파일명_정렬.js](Level2/17686_[3차]_파일명_정렬.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/17686) |
 | 17687 | n진수 게임 | [17687_n진수_게임.js](Level2/17687_n진수_게임.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/17687) |
 | 42576 | 완주하지 못한 선수 | [42576_완주하지_못한_선수.js](Level1/42576_완주하지_못한_선수.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/42576) |
+| 42577 | 전화번호 목록 | [42577_전화번호_목록.js](Level2/42577_전화번호_목록.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/42577) |
 | 42578 | 의상 | [42578_의상.js](Level2/42578_의상.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/42578) |
 | 42579 | 베스트앨범 | [42579_베스트앨범.js](Level3/42579_베스트앨범.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/42579) |
 | 42583 | 다리를 지나는 트럭 | [42583_다리를_지나는_트럭.js](Level2/42583_다리를_지나는_트럭.js) | [🔗](https://school.programmers.co.kr/learn/courses/30/lessons/42583) |