#include <iostream>
#include <fstream>
#include <algorithm>
#include <climits>
#include <cctype>
#include <cstdio>
#include <cstdlib>
#include <iomanip>
#include <cmath>
#include <ctime>
#include <vector>
#include <string>
#include <stack>
#include <queue>

#define ll long long
#define ull unsigned long lon
#define vi vector<int>

using namespace std;


void solve()
{
    int n;
    cin>>n;
    int* x=new int[n];
    
    for(int i=0; i<n ;i++)
    {
        cin>>x[i];
    }
    int nr=0;
    for(int i=0; i<n; i++)
    {
        if(x[i]==i)
        {
            nr++;
        }
    }
    
    if(nr%2==0)
    {
        cout<<"E: "<<nr/2<<endl;
    }
    else
    {
        cout<<"E: "<<nr/2+1<<endl;
    }

}


int main()
{
    int t;
    cin>>t;

    while(t--)
    {
        solve();
    }
}