Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {
	io := NewIo()
	defer io.Flush()
	n := io.NextInt()
	for i := 0; i < n; i++ {
		s, t := io.NextLine(), io.NextLine()
		io.Println(f(s, t))
	}
}

func f(s, t string) string {
	for i := len(s) - 1; i >= 0; i-- {
		switch s[i] {
		case 'C':
			t = strings.Join([]string{t[1:], string(t[0])}, "")
		case 'J':
			t = strings.Join([]string{string(t[len(t)-1]), t[:len(t)-1]}, "")
		case 'E':
			if len(t)%2 == 1 {
				t = strings.Join([]string{t[len(t)/2+1:], string(t[len(t)/2]), t[:len(t)/2]}, "")
			} else {
				t = strings.Join([]string{t[len(t)/2:], t[:len(t)/2]}, "")
			}
		case 'A':
			r := []rune(t)
			for i, n := 0, len(r); i < n/2; i++ {
				r[i], r[n-i-1] = r[n-i-1], r[i]
			}
			t = string(r)
		case 'M':
			r := []rune(t)
			for i := 0; i < len(r); i++ {
				if '0' <= r[i] && r[i] < '9' {
					r[i]++
				} else if r[i] == '9' {
					r[i] = '0'
				}
			}
			t = string(r)
		case 'P':
			r := []rune(t)
			for i := 0; i < len(r); i++ {
				if '0' < r[i] && r[i] <= '9' {
					r[i]--
				} else if r[i] == '0' {
					r[i] = '9'
				}
			}
			t = string(r)
		}
	}
	return t
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := make([]interface{}, 0, len(a))
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := make([]interface{}, 0, len(a))
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

C++: #include <bits/stdc++.h>
using namespace std;
/*{{{*/  //template
#define rep(i,n) for(int i=0;i<n;i++)
constexpr int INF = numeric_limits<int>::max()/2;
constexpr long long LINF = numeric_limits<long long>::max()/3;
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define all(v) (v).begin(),(v).end()
#define sz(x) (int)(x).size()
#define debug(x) cerr<<#x<<":"<<x<<endl
#define debug2(x,y) cerr<<#x<<","<<#y":"<<x<<","<<y<<endl
//struct fin{ fin(){ cin.tie(0); ios::sync_with_stdio(false); } } fin_;
struct Double{ double d; explicit Double(double x) : d(x){} };
ostream& operator<<(ostream& os,const Double x){ os << fixed << setprecision(20) << x.d; return os; }
template<typename T> ostream& operator<<(ostream& os,const vector<T>& vec){ os << "["; for(const auto& v : vec){ os << v << ","; } os << "]"; return os; }
template<typename T,typename U> ostream& operator<<(ostream& os,const pair<T,U>& p){ os << "(" << p.first << ","<< p.second <<")"; return os; }
template<typename T> ostream& operator<<(ostream& os,const set<T>& st){ os<<"{"; for(T v:st) os<<v<<","; os <<"}"; return os; }
template<typename T,typename U> inline void chmax(T &x,U y){ if(y>x) x = y; }
template<typename T,typename U> inline void chmin(T &x,U y){ if(y<x) x = y; }
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
ll gcd(ll a,ll b){ if(b==0) return a; else return gcd(b,a%b); }
//constexpr double eps = 1e-14; 
constexpr double eps = 1e-10; 
constexpr ll mod = 1e9+7;
const int dx[]={1,0,-1,0} ,dy[] = {0,1,0,-1};
/*}}}*/

string J(string t){
    string ret = t.substr(sz(t)-1,1);
    ret += t.substr(0,sz(t)-1);
    return ret;
}

string C(string t){
    string ret = t.substr(1,sz(t)-1);
    ret.pb(t[0]);
    return ret;
}

string E(string s){
    if(s.size()%2==0){
        int t = s.size();
        string s1 = s.substr(0,t/2);
        string s2 = s.substr(t/2,t/2);

        return s2+s1;
    }else{
        int t = s.size();
        string s1 = s.substr(0,t/2);
        string s2 = s.substr(t/2+1,t/2);
        char c = s[t/2];
        string ret = s2;
        ret.pb(c);
        ret += s1;
        return ret;
    }
}

string A(string s){
    string ret = s;
    reverse(all(ret));
    return ret;
}

string P(string s){
    for(int i=0;i<sz(s);i++){
        if('1'<=s[i] and s[i]<='9') s[i]--;
        else if(s[i]=='0') s[i]='9';
    }
    return s;
}

string M(string s){
    for(int i=0;i<sz(s);i++){
        if('0'<=s[i] and s[i]<'9'){
            s[i]++;
        }else if(s[i]=='9'){
            s[i]='0';
        }
    }
    return s;
}

void solve(){
    string s,t;
    cin >> s >> t;

    for(int i=sz(s)-1;i>=0;i--){
        string u;
        if(s[i]=='J') t = J(t);
        if(s[i]=='C') t = C(t);
        if(s[i]=='E') t = E(t);
        if(s[i]=='A') t = A(t);
        if(s[i]=='P') t = P(t);
        if(s[i]=='M') t = M(t);
    }
    cout << t << endl;
}

int main(){
//    string s;
//    cin >> s;
//    cout << P(s) << endl;
//    return 0;
    int N;
    cin >> N;
    rep(i,N) solve();
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
#include <utility>
#include <string>

#define REP(i,a,b) for(int i=int(a);i<int(b);i++)

using namespace std;

typedef long long int lli;
typedef pair<int,int> pii;

int main () {
    int n;
    cin >> n;
    while (n--) {
        string kings;
        cin >> kings;
        string message;
        cin >> message;
        for (int i = kings.size() - 1; i >= 0; i--) {
            if (kings[i] == 'J' && message.size() > 1) {
                message = message.substr(message.size() - 1, 1) + message.substr(0, message.size() - 1);
            }
            if (kings[i] == 'C' && message.size() > 1) {
                message = message.substr(1) + message.substr(0, 1);
            }
            if (kings[i] == 'E') {
                if (message.size() % 2) {
                    message = message.substr((message.size() + 1) / 2) + message[message.size() / 2] + message.substr(0, message.size() / 2);
                } else {
                    message = message.substr((message.size() + 1) / 2) + message.substr(0, message.size() / 2);
                }
            }
            if (kings[i] == 'A') {
                reverse(message.begin(), message.end());
            }
            if (kings[i] == 'P') {
                REP (j, 0, message.size()) {
                    if ('0' <= message[j] && message[j] <= '9') {
                        message[j] = max(message[j] - 1, (int)'0');
                    }
                }
            }
            if (kings[i] == 'M') {
                REP (j, 0, message.size()) {
                    if ('0' <= message[j] && message[j] <= '9') {
                        message[j] = min(message[j] + 1, (int)'9');
                    }
                }
            }
        }
        cout << message << endl;
    }

    return 0;
}