title: Lexicographical Concatenation Substrings String
signature: fun lexicographicalConcatenationSubstringsString(s: String): String {
test_code: package main
  
  import kotlin.text.*
  import kotlin.math.*
  
  
  // SOLUTION CODE
  // ===================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE
  // ===================================
  fun validateSolution(actual:String, expected:String):Boolean{
    return actual.equals(expected)
  }
  fun driver(s: String, expected:String):String {
      try{
        if (validateSolution(PLACEHOLDER_FN_NAME(s), expected)) {
                return "PASSED"
        }
        return "FAILED"
      } catch (e: Exception){
        return e::class.simpleName as String
      }
  
  }
  
  fun main() {
      var result: String = ""
      result = driver("sqGOi", "GGOGOiOOiiqqGqGOqGOissqsqGsqGOsqGOi")
      println("TEST-0...${result}")
      
      result = driver("ZhWXUKmeiI", "IKKmKmeKmeiKmeiIUUKUKmUKmeUKmeiUKmeiIWWXWXUWXUKWXUKmWXUKmeWXUKmeiWXUKmeiIXXUXUKXUKmXUKmeXUKmeiXUKmeiIZZhZhWZhWXZhWXUZhWXUKZhWXUKmZhWXUKmeZhWXUKmeiZhWXUKmeiIeeieiIhhWhWXhWXUhWXUKhWXUKmhWXUKmehWXUKmeihWXUKmeiIiiImmemeimeiI")
      println("TEST-1...${result}")
      
      result = driver("tjP kR", "  k kRPP P kP kRRjjPjP jP kjP kRkkRttjtjPtjP tjP ktjP kR")
      println("TEST-2...${result}")
      
      result = driver("qJPHNSJOUj", "HHNHNSHNSJHNSJOHNSJOUHNSJOUjJJJOJOUJOUjJPJPHJPHNJPHNSJPHNSJJPHNSJOJPHNSJOUJPHNSJOUjNNSNSJNSJONSJOUNSJOUjOOUOUjPPHPHNPHNSPHNSJPHNSJOPHNSJOUPHNSJOUjSSJSJOSJOUSJOUjUUjjqqJqJPqJPHqJPHNqJPHNSqJPHNSJqJPHNSJOqJPHNSJOUqJPHNSJOUj")
      println("TEST-3...${result}")
      
          
  }
  
  main()
source_py: def lexicographical_concatenation_substrings_string(s):
      n = len(s)
      sub_count = ((n * (n + 1)) // 2)
      arr = ([0] * sub_count)
      index = 0
      for i in range(n):
          for j in range(1, ((n - i) + 1)):
              arr[index] = s[i:(i + j)]
              index += 1
      arr.sort()
      res = ''
      for i in range(sub_count):
          res += arr[i]
      return res
source_cpp: string lexicographical_concatenation_substrings_string(string s) {
    int n = s . length ( );
    int sub_count = n * ( n + 1 ) / 2;
    string arr [ sub_count ];
    int index = 0;
    for ( int i = 0;
    i < n;
    i ++ ) for ( int len = 1;
    len <= n - i;
    len ++ ) arr [ index ++ ] = s . substr ( i, len );
    sort ( arr, arr + sub_count );
    string res = "";
    for ( int i = 0;
    i < sub_count;
    i ++ ) res += arr [ i ];
    return res;
  }