프로그래머스 - 문자열 겹쳐쓰기
class Solution {
public String solution(String my_string, String overwrite_string, int s) {
String str = my_string.substring( 0, s) + overwrite_string;
String str1 = my_string.substring(overwrite_string.length() + s, my_string.length());
String answer = str + str1;
return answer;
}
}