HackerRank(greedy): Minimum Absolute Difference in an Array

Problem:

Consider an array of integers, A = a0, a1, a2....an-1. We define the absolute difference between two elements, ai and aj
(where ai not equal to aj ), to be the absolute value of ai-aj.

Given an array of n integers, find and print the minimum absolute difference between any two elements in the array.

Input Format

The first line contains a single integer denoting (the number of integers).
The second line contains space-separated integers describing the respective values of a0, a1....an-1 .

Constraints

- 2 <= n <= 10^5
- -10^9 <= ai <= 10^9

Output Format

Print the minimum absolute difference between any two elements in the array.

Sample Input 0

3
3 -7 0

Sample Output 0

3

Solutions: Note: Simple O(n^2) solution won't work because of time constraints. So, use this below O(N logN) solution which uses sorting the array first, then uses O(N) to compare adjacent differences.

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <climits>
using namespace std;

int main() {
    int n;
    long long min = INT_MAX;
    cin>>n;
    vector<long long>arr(n);
    for(int i=0; i<n; i++)
    cin>>arr[i];
    sort(arr.begin(), arr.end());
    for(int i=0;i<n-1;i++)
    if(min>abs(arr[i]-arr[i+1]))
    min=abs(arr[i]-arr[i+1]);
    cout<<min;
    return 0;
}