(good pairs) assign the value of one array to another array

Title Description

Give you an array of integers nums. 

If a set of numbers (i, j) Satisfy nums[i] == nums[j] And i < j, It can be considered as a group of good pairs .  

Please calculate the number of such good pairs . 

Input

The input contains only one set of data ;  

The first line contains only a positive integer n, Represents this array nums Its size is n (1 ≤ n ≤ 1000);  

The second line contains n It's an integer nums[i] (1 ≤ nums[i] ≤ 1000). 

Output

Output the number of pairs . 

The sample input

6
1 2 3 1 1 3

Sample output

4

Tips

For example, enter , There are four groups of good pairs , Namely a1 == a4,a1 == a5,a3 == a6,a4 == a5 .

#include <stdio.h>
int main()
{
    int n,a[1000],b[1000];
    scanf("%d",&n);
    for(int i=0;i<n;i++){
        scanf("%d",&a[i]);
    }
    for(int i=0;i<n;i++){
        b[i]=a[i];
        }
    int count=0;
    for(int i=0;i<n;i++)
    for(int j=i+1;j<n;j++){
        if(a[i]==b[j])
            count++;
    }
    printf("%d",count);
}