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 <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <vector>
#include <string>
#include <queue>
#include <algorithm>
#include <math.h>
#include <utility>
#include <set>
#include <map>
#include <cstring>
#include <cstdio>
#include <stack>
#define INF 1000000000
#define rep(i,n) for(int i =0;i<n;i++)
using namespace std;
typedef long long int ll;

string A(string s){
    reverse(s.begin(),s.end());
    return s;
}

string J(string s){
    string ss = s.substr(s.length()-1,1),sss=s.substr(0,s.length()-1);
    return ss+sss;
}

string C(string s){
    string ss = s.substr(0,1),sss=s.substr(1,s.length()-1);
    return sss+ss;
}

string E(string s){
    if(s.length()%2==0){
        string ss = s.substr(0,s.length()/2);
        string sss = s.substr(s.length()/2,s.length()/2);
        return sss+ss;
    }else{
        string ss = s.substr(0,s.length()/2);
        string tt = s.substr(s.length(),1);
        string sss = s.substr(s.length()/2+1,s.length()/2);
        return sss+tt+ss;
    }
}

string P(string s){
    for (int i=0; i<s.length(); i++) {
        if (s[i]=='9' or s[i]=='1' or s[i]=='2' or s[i]=='3' or s[i]=='4' or s[i]=='5' or s[i]=='6' or s[i]=='7' or s[i]=='8') {
            s[i]=(char)((int)s[i]-1);
            continue;
        }
        if (s[i]=='0') {
            s[i]='9';
        }
    }
    return s;
}

string M(string s){
    for (int i=0; i<s.length(); i++) {
        if (s[i]=='0' or s[i]=='1' or s[i]=='2' or s[i]=='3' or s[i]=='4' or s[i]=='5' or s[i]=='6' or s[i]=='7' or s[i]=='8') {
            s[i]=(char)((int)s[i]+1);
            continue;
        }
        if (s[i]=='9') {
            s[i]='0';
        }
    }
    return s;
}


int main(){
    int n;
    cin >> n;
    for (int wq=0; wq<n; wq++) {
        string t,s;
        cin >> t >>s;
        for (int i= t.length()-1; i>=0; i--) {
            if(t[i]=='J') s = J(s);
            if(t[i]=='C') s = C(s);
            if(t[i]=='E') s = E(s);
            if(t[i]=='A') s = A(s);
            if(t[i]=='P') s = P(s);
            if(t[i]=='M') s = M(s);
        }
        cout << s <<endl;
    }
}

C++: #include <bits/stdc++.h>
using namespace std;
#define all(a) (a).begin(),(a).end()

int main()
{
	int n;
	cin >> n;
	while (n--){
		string m, s;
		cin >> m >> s;
		reverse(all(m));
		for (int i = 0; i < m.size(); i++){
			if (m[i] == 'C'){
				string a(s, 0, 1);
				string b(s, 1, s.size() - 1);
				s = b + a;
			}
			else if (m[i] == 'J'){
				string a(s, 0, s.size() - 1);
				string b(s, s.size() - 1, 1);
				
				//cout << s << " " << a << " " << b << endl;
				
				s = b + a;
			}
			else if (m[i] == 'E'){
				string a(s, 0, s.size() / 2);
				string b(s, s.size() / 2, s.size() % 2);
				string c(s, s.size() / 2 + s.size() % 2, s.size() / 2);
				s = c + b + a;
			}
			else if (m[i] == 'A'){
				reverse(all(s));
			}
			else if (m[i] == 'M'){
				for (int j = 0; j < s.size(); j++){
					if (s[j] >= '0' && s[j] <= '8'){
						s[j]++;
					}
					else if (s[j] == '9'){
						s[j] = '0';
					}
				}
			}
			else if (m[i] == 'P'){
				for (int j = 0; j < s.size(); j++){
					if (s[j] >= '1' && s[j] <= '9'){
						s[j]--;
					}
					else if (m[i] == '0'){
						s[i] = '9';
					}
				}
			}
		}
		
		cout << s << endl;
	}
	
	return 0;
}