// Thank God!
#include <bits/stdc++.h>
using namespace std;

// Aliases for simple data types
using ll = long long;
using dd = long double;
using mpi = map<int, int>;
using mpl = map<ll, ll>;
using ull = unsigned long long;

// Constant definitions
#define PI 3.14159265358979323
#define E 2.7182818284590
#define all(x) x.begin(), x.end()

// BIG NUMBERS (MODULAR)
const ll MOD1 = 998244353;
const ll MOD2 = (ll)1e9 + 7;

// simplified aliases for vectors,pairs
template <class T>
using v = vector<T>;
template <class T>
using p = pair<T, T>;

// overloaded instream operators
template <class T1, class T2>
istream &operator>>(istream &in, pair<T1, T2> &p)
{
    in >> p.first >> p.second;
    return in;
}
template <class T>
istream &operator>>(istream &in, v<T> &v)
{
    for (auto &x : v)
        in >> x;
    return in;
}

// MULTITEST TOGGLE
const bool test = true;
// INTERACTIVE TOGGLE
const bool interactive = false;
/*-------------------------------------------------------------------------------*/

const int MAXN = 1e5 + 4;
v<v<int>> adj(MAXN);

// dp[u][0] represents NO music
//  dp[u][1] represents MUSIC
v<v<ll>> dp(MAXN, v<ll>(2));
string status;

void dfs(int node, int prev)
{
    if (status[node] == 'P')
    {
        dp[node][0] = 1e18; // need to party
    }
    else if (status[node] == 'S')
    {
        dp[node][1] = 1e18; // need to sleep
    }
    for (auto &x : adj[node])
    {
        if (x != prev)
        {
            dfs(x, node);
            if (status[node] != 'P')
            {
                dp[node][0] += min(dp[x][0], dp[x][1] + 1);
            }
            if (status[node] != 'S')
            {
                dp[node][1] += min(dp[x][1], dp[x][0] + 1);
            }
        }
    }
}
void solve()
{
    int n;
    cin >> n;
    for (int i = 1; i <= n; i++)
    {
        adj[i].clear();
        dp[i].clear();
        dp[i].push_back(0);
        dp[i].push_back(0);
    }
    int x;
    for (int i = 2; i <= n; i++)
    {
        cin >> x;
        adj[i].push_back(x);
        adj[x].push_back(i);
    }
    cin >> status;
    status = "." + status;
    dfs(1, -1);
    cout << min(dp[1][0], dp[1][1]) << "\n";
}

int main()
{
    /*Command Line
    g++ forkiespad.cpp -o forkiespad
    forkiespad.exe
    */

    // file input
    if (interactive)
    {
        freopen("input.txt", "r", stdin);
    }
    ios::sync_with_stdio(false);
    cin.tie(0);

    // testcases
    int t;
    if (test)
    {
        cin >> t;
    }
    else
        t = 1;

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

/*
-try out more cases
-attack the problem creatively/at different angles
-what am i missing?
-CHECK YOUR CODE
-pay attention to BOUNDS
-errors - out of bounds, edge case(n=0, n=1?), integer overflow, etc.
-WHEN IN DOUBT, USE LONG LONG
-check the for loops
-watch out for division errors (use double and ll when needed)
*/
// Thank God!