week39 풀었습니다.

sgoldenbird/level0/글자_이어_붙여_문자열_만들기.js

@@ -0,0 +1,9 @@
+function solution(my_string, index_list) {
+  let answer = "";
+
+  for (i = 0; i < index_list.length; i++) {
+    answer += my_string[index_list[i]];
+  }
+
+  return answer;
+}

sgoldenbird/level0/문자열_곱하기.js

@@ -0,0 +1 @@
+test;

sgoldenbird/level0/접두사인지_확인하기.js

@@ -0,0 +1,3 @@
+function solution(my_string, is_prefix) {
+  return my_string.startsWith(is_prefix) ? 1 : 0;
+}

sgoldenbird/level1/문자열_내_p와_y의_개수.js

@@ -0,0 +1,16 @@
+function solution(s) {
+  const lowerS = s.toLowerCase();
+  let countP = 0;
+  let countY = 0;
+
+  for (const char of lowerS) {
+    if (char === "p") {
+      countP++;
+    }
+    if (char === "y") {
+      countY++;
+    }
+  }
+
+  return countP === countY ? true : false;
+}