#include<bits/stdc++.h>
using namespace std;
int main()
{
	ios_base::sync_with_stdio(false);
//	cin.tie(0);
	int T;
	cin>>T;
	while(T--)
	{
		int n,m;
		cin>>n>>m;
		vector<pair<int,int>> ans;
		stack<int> s1,s2;
		int c1=0,c2=0;
		for(int i=1;i<=n;i++)
		{
			int x;
			cin>>x;
			if(c1==0)s1.push(i),c1=x;
			else if(c1==x and c2==0)s1.push(i);
			else if(c1==x)
			{
				int u;
				while(not s2.empty())
				{
					u=s2.top();s2.pop();
					ans.emplace_back(u,i);
				}
				s2.push(u);
				while(not s1.empty() and s1.top()>u)
				{
					s1.pop();
				}
				s1.push(i);
			}
			else if(c2==0 or c2==x)
			{
				int u;
				while(not s1.empty())
				{
					u=s1.top();s1.pop();
					ans.emplace_back(u,i);
				}
				s1.push(u);
				while(not s2.empty() and s2.top()>u)
				{
					s2.pop();
				}
				s2.push(i);
				c2=x;
			}
			else
			{
				int u,v;
				while(not s1.empty())
				{
					u=s1.top();s1.pop();
					ans.emplace_back(u,i);
				}
				while(not s2.empty())
				{
					v=s2.top();s2.pop();
					ans.emplace_back(v,i);
				}
				if(u<v)
				{
					s1.push(u);
					s2.push(i);
					c2=x;
				}
				else
				{
					s1.push(i);
					s2.push(v);
					c1=x;
				}
			}
		}
		cout<<ans.size()<<"\n";
		for(auto [u,v]:ans)
			cout<<u<<' '<<v<<"\n";
	}
	return 0;
}