View Code of Problem 3929

#include<stdio.h>

int main(){
	int T;
	scanf("%d",&T);
	while(T--){
		int n;
		scanf("%d",&n);
		int i,a[n],sum;
		for(i=0;i<n;i++){
			scanf("%d",&a[i]);
		} 
		if(n>1){
			sum=a[0];
			for(i=1;i<n;i++){
				sum=sum^a[i];
			}
			printf("%d\n",sum);
		}
		else if(n==1){
			printf("%d\n",a[0]);
		}
	
	}
}