Help me in solving MISSP problem

help
,
1

My issue

im not understood the problem

My code

#include <stdio.h>

int main(void) {
	// your code goes here
	int t;
	scanf("%d",&t);
	while(t--)
	{
	        int n;
	        scanf("%d",&n);
	        int a[n];
	        for(int i=0;i<n;i++)
	        {
	            scanf("%d",a[i]);
	            
	        }
	}
	
	
	return 0;
}

Problem Link: MISSP Problem - CodeChef

2

@mohansai73
the logic for this is, u have to print the number that has odd frequency.