Hackerrank - Permuting Two Arrays Solution

Consider two -element arrays of integers,  and . You want to permute them into some  and  such that the relation  holds for all  where . For example, if , , and , a valid  satisfying our relation would be  and ,  and .

You are given  queries consisting of , , and . For each query, print YES on a new line if some permutation ,  satisfying the relation above exists. Otherwise, print NO.

Function Description

Complete the twoArrays function in the editor below. It should return a string, either YES or NO.

twoArrays has the following parameter(s):

• k: an integer
• A: an array of integers
• B: an array of integers

Input Format

The first line contains an integer , the number of queries.

The next  sets of  lines are as follows:

• The first line contains two space-separated integers  and , the size of both arrays  and , and the relation variable.
• The second line contains  space-separated integers .
• The third line contains  space-separated integers .

Constraints

Output Format

For each query, print YES on a new line if valid permutations exist. Otherwise, print NO.

Sample Input

2
3 10
2 1 3
7 8 9
4 5
1 2 2 1
3 3 3 4

Sample Output

YES
NO

Explanation

We perform the following two queries:

, , and . We permute these into  and  so that the following statements are true:

• Thus, we print YES on a new line.

1. , , and . To permute  and  into a valid  and , we would need at least three numbers in  to be greater than ; as this is not the case, we print NO on a new line.

Solution in Python

def twoArrays(k, A, B):
    A = sorted(A)
    B = sorted(B, reverse=True)
    for x,y in zip(A,B):
        if x+y<k:
            return "NO"
    return "YES"

for _ in range(int(input())):
    n, k = map(int, input().split())
    A = list(map(int, input().split()))
    B = list(map(int, input().split()))
    print(twoArrays(k, A, B))