P14_XennyAndPartiallySortedStrings.py

# Xenny had a list of N strings of equal length. He wanted to sort them by the first M characters only. That
# means, while sorting the list of strings, he only wanted to consider the first M characters of each string.
# Help Xenny to find out the Kth string in the list after he sorts them.
#
# Note: Xenny wanted to perform stable sorting.
# Stable sorting algorithms maintain the relative order of records with equal keys (i.e. values). That is, a
# sorting algorithm is stable if whenever there are two records R and S with the same key and with R
# appearing before S in the original list, R will appear before S in the sorted list.
#
# Input
#
# First line contains a single integer - T, which represents the number of testcases.
# T testcases follow.
# Each testcase is of the following format:
# First line contains 3 space-separated integers - N, K and M.
# N is the total number of strings Xenny has.
# K is the index of the string in the list after sorting, which Xenny has to find.
# M is the number of characters based on which sorting will be done by Xenny.
# Then next N lines contain N strings ( each line will contain one string ) .
#
# Output
#
# For each testcase, print the Kth string in the sorted list in a new line.
#
# Constraints
#
# 1 ≤ T ≤ 50
# 1 ≤ N ≤ 103
# 1 ≤ Max Length of each String ≤ 103
# 1 ≤ M ≤ Max Length
# M ≤ Max Length of each String ≤ 103
#
# SAMPLE INPUT
# 1
# 3 1 3
# abcdef
# abcaaa
# aabaaa
#
# SAMPLE OUTPUT
# aabaaa

for _ in range(int(input())):
	n, k, m = input().split()
	strings = []
	for i in range(int(n)):
		strings.append(input())

	array = sorted(strings, key = lambda x: x[:int(m)])
	print(array[int(k) - 1])