//Don't have to see. start------------------------------------------
var read = require('readline').createInterface({
	input: process.stdin, output: process.stdout
});
var obj; var inLine = []; var outputList = [];var retcode = new Set();
read.on('line', function(input){
	var tmp = input.split(' ');
	for(var i = 0; i < tmp.length; i++){
		inLine.push(tmp[i]);
		if(i == tmp.length - 1){
			retcode.add(inLine.length);
		}
	}
});
read.on('close', function(){
	obj = init(inLine);
	console.error('\n↑入力 ↓出力');
	Main();
	console.log(myconv(outputList, 9));
});
function makeClone(obj){return (obj instanceof Set) ? new Set(Array.from(obj)) : JSON.parse(JSON.stringify(obj));}
function nextArray(size, code){
	var ret = new Array(size);
	for(var i = 0; i < size; i++){
		if(code == 'int'){
			ret[i] = nextInt();
		}else{
			ret[i] = next();
		}
	}
	return ret;
}
function nextIntArray(size){return nextArray(size, 'int');} function nextStrArray(size){return nextArray(size, 'str');}
function nextCharArray(){return myconv(next(),6);}
function next(){return obj.next();} function hasNext(){return obj.hasNext();} function nextInt(){return myconv(next(),1);}
function init(input){  
	return {
		list : input, index : 0, max : input.length,
		hasNext : function(){return (this.index < this.max);},
		next : function(){if(this.hasNext()){return this.list[this.index++];}else{throw 'ArrayIndexOutOfBoundsException ‚There is no more input';}},
		isReturn : function(){return retcode.has(this.index);}
	};
}
function myout(s){outputList.push(s);}
function myerr(s){console.error('debug:' + require('util').inspect(s,false,null));}
function isReturn(){return obj.isReturn();}
//param "no" is
//unknown or outlier : return i. 1: parseInt.
//2: split space. 4: split space and parseInt.
//6: split 1 character. 7: split 1 character and parseInt.
//8: join space. 9: join nextline. 0: join no character.
function myconv(i,no){try{switch(no){case 1:return parseInt(i);case 2:return i.split(' ');case 4:return i.split(' ').map(Number);case 6:return i.split('');case 7:return i.split('').map(Number);case 8:return i.join(' ');case 9:return i.join('\n');case 0:return i.join('');default:return i;}}catch(e){return i;}}

//Don't have to see. end------------------------------------------
function Main(){
	var t = nextInt();
	for(var i = 0; i < t; i++){
		var N = nextInt();
		var list = nextIntArray(N);
		var queue = [];
		for(var j = 0; j < N; j++){
			if((list[j] < list[(j + 1) % N] && list[(j + 1) % N] > list[(j + 2) % N]) || (list[j] > list[(j + 1) % N] && list[(j + 1) % N] < list[(j + 2) % N])){
				if(list[j] != list[(j + 2) % N]){
					queue.push({
						v : list[j],
						used : [j, (j + 1) % N, (j + 2) % N]
					});
				}
			}
		}
		queue.sort(function(a,b){
			return b.v - a.v;
		});
		var output = 0;
		for(var j = 0; j < queue.length; j++){
			var node = queue[j];

			if(list[node.used[0]] != -1 && list[node.used[1]] != -1 && list[node.used[2]] != -1){
				output += node.v;
				list[node.used[0]] = -1;
				list[node.used[1]] = -1;
				list[node.used[2]] = -1;
			}
		}
		myout(output);
	}
}