n=int(input())
a=list(map(int,input().split()))
a.sort()
sum=0
for i in range(1,n,2):
sum+=a[i]-a[i-1]
print(sum)#include <iostream>
#include<vector>
#include<algorithm>
using namespace std;
int main()
{
vector<int> v;
int n,x,c=0;
cin>>n;
while(n--){
cin>>x;
v.push_back(x);
}
sort(v.begin(),v.end());
for(int i=0;i<v.size();i+=2){
c+=v[i+1]-v[i];
}
cout <<c;
return 0;
}
33. Search in Rotated Sorted Array | 17. Letter Combinations of a Phone Number |
5. Longest Palindromic Substring | 3. Longest Substring Without Repeating Characters |
1312. Minimum Insertion Steps to Make a String Palindrome | 1092. Shortest Common Supersequence |
1044. Longest Duplicate Substring | 1032. Stream of Characters |
987. Vertical Order Traversal of a Binary Tree | 952. Largest Component Size by Common Factor |
212. Word Search II | 174. Dungeon Game |
127. Word Ladder | 123. Best Time to Buy and Sell Stock III |
85. Maximal Rectangle | 84. Largest Rectangle in Histogram |
60. Permutation Sequence | 42. Trapping Rain Water |
32. Longest Valid Parentheses | Cutting a material |
Bubble Sort | Number of triangles |
AND path in a binary tree | Factorial equations |
Removal of vertices | Happy segments |
Cyclic shifts | Zoos |
Build a graph | Almost correct bracket sequence |