using System;

namespace BasicFormat {
    class Program {
        static int lineCount;
        static string indent;

        static void Main() {
            lineCount = int.Parse(Console.ReadLine());
            string[] inputCode = new string[lineCount];
            indent = Console.ReadLine();
            int i = 0;
            string line;
            while (i < lineCount) {
                line = Console.ReadLine();
                inputCode[i] = line;
                i++;
            }
            Console.Write(FormatCode(inputCode));
        }

        static string FormatCode(string[] lines) {
            string result = "";
            string emptyLine, startsWith;
            int indentLevel = 0;
            for (int i = 0; i < lineCount; i++) {
                emptyLine = string.Join("", lines[i].Split('»', '·'));
                startsWith = emptyLine.Split()[0];
                if (startsWith == "ENDIF" || startsWith == "NEXT") {
                    indentLevel -= 1;
                }
                for (int j = 0; j < indentLevel; j++) {
                    result += indent;
                }
                result += emptyLine + "\n";
                if (startsWith == "IF" || startsWith == "FOR") {
                    indentLevel += 1;
                }
            }
            return result;
        }
    }
}