CL16BD - Editorial

cl16bd
colg2016
easy
editorial
greedy
sorting

#1

PROBLEM LINK:

Practice
Contest

Author: Subham Das
Tester: Soumik Sarkar
Editorialist: Subham Das

DIFFICULTY:

EASY

PREREQUISITES:

Array, Sorting

PROBLEM:

Given two integer arrays C and D both of length N, establish a one-to-one correspondence between the elements of C and D so as to maximize the number of pairings where the element of C is greater than the element from D in a pair.

EXPLANATION

The value of n and the array C, D which contains the power of Chef’s cards and Devu’s cards respectively are given within every test case. The first step would be to sort the array C and D in increasing order. Then number of times Chef’s cards have more value than Devu’s cards can be found out with the help of the following greedy algorithm:

j = 0;
for i  0 to n-1
    if(C* > D[j])
        j = j+1;

After this printing the value of j would yield the answer as (j-1) is the maximum value upto which all values of array D are lesser than some corresponding value in array C.

Complexity: \mathcal{O}(N\, log\, N)

AUTHOR’S AND TESTER’S SOLUTIONS:

Author’s solution can be found here.
Tester’s solution can be found here.