void quickSort(int left,int right){
	int mid = a[left];
	int i = left;
	int j = right;
//	int t;
	while(i<j){
		while(a[j]>mid && i<j) j--;
		if(i<j){
			a[i] = a[j];
			i++;
		}
		while(a[i]<mid && i<j) i++;
		if(i<j){
			a[j] = a[i];
			j--;
		}
	}
	a[i] = mid;
	if(left<right) quickSort(left,i-1);
	if(left<right) quickSort(i+1,right);
}